MAPS OF HISTORY · IB HISTORY · CLIMATE AND INNOVATION
IB HISTORY · C. 790 – 1521 · 12 CHAPTERS
IB History: The Norse and the Aztecs — notes, maps and essay plans
In the warm centuries Norse farmers sailed to Greenland; they left as the cold returned. In another demanding climate, the Mexica made a city of 200,000 from a salty lake.
This page gathers the atlas’s IB notes: where each of its 12 chapters fits the syllabus, the concepts and evidence it supports, practice questions with model essay plans, primary sources, and starting points for the Internal Assessment.
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Where it fits the course
Every chapter’s IB notes name the parts of the course it serves. Across the atlas they add up to this: It is the paired atlas for the Paper 1 Focused Study Climate and Innovation, whose page holds a free source-question set.
- Paper 1 · Climate and Innovation · 12 CHAPTERS
- Paper 2 · Conflict · 1 CHAPTER
- Paper 2 · Innovation and Transformation · 11 CHAPTERS
Chapter by chapter
Across its 12 chapters, the atlas holds 72 points of evidence and 46 primary sources. Here you can read all the evidence for chapters 1 and 2. For each later chapter there is one point and the practice question; the rest is in the atlas. Select a chapter title to open its free page and read the full explanation.
1. Climate as a Force in History
CHAPTER 1 · c. 950–1450 · CONCEPTS: CAUSATION, SIGNIFICANCE, PERSPECTIVES
EVIDENCE TO USE · ALL 6 POINTS (A FREE CHAPTER)
- In 2009, Michael Mann’s team found warmth around the North Atlantic in 950–1250 alongside cool conditions in parts of the tropical Pacific. The Medieval Climate Anomaly was therefore a regional pattern, with cool as well as warm areas.
- Gifford Miller’s team placed the onset of the Little Ice Age in 1275–1300, following a cluster of large volcanic eruptions. They argued that expanding sea ice kept summers cold long after the volcanic haze cleared.
- The GISP2 core was drilled at Summit in Greenland from 1989 to 1993, reaching bedrock at 3,053 metres. Its near-annual temperature record gives historians evidence independent of the sagas and annals they can test against it.
- Midge remains from Scoop Lake near the Eastern Settlement suggest summers about 1.5 °C warmer in 900–1400. Lake 578, by contrast, shows little temperature change but a drying trend. Even records from the same region can point to different conditions.
- David Stahle’s team published the Mexican Drought Atlas in 2016. It confirms a great drought across central Mexico in 1452–54, when Mexica chronicles describe frost, hunger and the famine of One Rabbit.
- In 1257–58 Samalas erupted in Indonesia, in one of the largest eruptions of the last thousand years. It was part of the cluster that Miller’s team links to the onset of colder North Atlantic conditions.
2. The Ship and the Sea Road
CHAPTER 2 · c. 790–900 · CONCEPTS: CAUSATION, CHANGE, SIGNIFICANCE
EVIDENCE TO USE · ALL 6 POINTS (A FREE CHAPTER)
- The Oseberg ship was built around 820 and buried in 834. It was 21.5 metres long, with fifteen pairs of oars. Its clinker hull, made from overlapping riveted planks, flexed with the waves and drew only about a metre of water.
- A ship depended on more than its builders. Lise Bender Jørgensen calculates that a warship’s woollen sail required more than 1.5 tonnes of wool and fifty to sixty years of labour: behind the vessel stood an entire farming economy.
- Only about 3 percent of Norway can be ploughed. James Barrett argued in 2008 that a surplus of young unmarried men who lacked land and bride-wealth made raiding attractive once ships made it possible.
- Eastern routes offered access to wealth. Scandinavian finds include hundreds of thousands of Islamic silver coins, known as dirhams; hundreds of silver hoards have been found on Gotland alone. Such finds show why traders and raiders might be drawn east.
- Around 890 the Norwegian chieftain Ohthere told King Alfred that he hunted walrus for their tusks and hides and took tribute from the Sámi. Hunting, tribute, trade and raiding belonged to the same northern economy.
- Within two generations, Norse activity had moved from raids to settlement and rule. Dublin became a Norse town from 841, and a great army took York in 866, laying foundations for the Danelaw.
3. Iceland: A Society on a Volcanic Island
CHAPTER 3 · 870–1000 · CONCEPTS: CHANGE, CONSEQUENCE, PERSPECTIVES
EVIDENCE TO USE · 1 OF 6
- Ari Þorgilsson wrote Íslendingabók in the 1120s, long after settlement. He says the island was settled within sixty winters and describes it as wooded “between fell and fore-shore”, preserving an account of a landscape different from the later one.
Practice question: How did Norse settlement change Iceland’s environment and society between 870 and 1100?
5 more points of evidence, 4 primary sources and the model plan for this question are in the IB notes of chapter 3 in the atlas.
4. Greenland and Vinland
CHAPTER 4 · 985–1050 · CONCEPTS: CAUSATION, SIGNIFICANCE, PERSPECTIVES
EVIDENCE TO USE · 1 OF 6
- In 985 or 986, Erik the Red led 25 ships from Iceland toward Greenland; 14 arrived. Settlers built about 500 farms in the Eastern Settlement and 75–100 in the Western Settlement, using the warm inner fjords for pasture.
Practice question: Compare and contrast the reasons for Norse settlement in Greenland with explanations for the abandonment of Vinland.
5 more points of evidence, 4 primary sources and the model plan for this question are in the IB notes of chapter 4 in the atlas.
5. Living with the Cold
CHAPTER 5 · 1250–1450 · CONCEPTS: CAUSATION, CHANGE, PERSPECTIVES
EVIDENCE TO USE · 1 OF 6
- What did the Greenlanders eat as conditions changed? Bone chemistry from 123 Norse skeletons suggests a marked shift: marine food rose from roughly 15–50 percent of the early colony’s diet to 50–80 percent by the fourteenth century. The Greenlanders were eating far more seal.
Practice question: To what extent was climate change the main reason Norse Greenland was abandoned?
5 more points of evidence, 4 primary sources and the model plan for this question are in the IB notes of chapter 5 in the atlas.
6. What the Norse Left
CHAPTER 6 · c. 1100–1450 · CONCEPTS: CONTINUITY, SIGNIFICANCE, CHANGE
EVIDENCE TO USE · 1 OF 6
- Around the year 1000, fish bones at English sites show a sudden rise in sea fish. James Barrett calls this change the fish event horizon. Isotope studies trace much of the later cod to northern Norway, where the stockfish trade had its home.
Practice question: Discuss how far the most lasting Norse innovations spread risk across many resources.
5 more points of evidence, 3 primary sources and the model plan for this question are in the IB notes of chapter 6 in the atlas.
7. An Empire Built on a Lake
CHAPTER 7 · 1325–1428 · CONCEPTS: CAUSATION, CHANGE, PERSPECTIVES
EVIDENCE TO USE · 1 OF 6
- The Basin of Mexico lies about 2,240 metres above sea level and covers roughly 7,500–9,600 square kilometres. At high water its linked lakes spread over some 1,000–1,500 square kilometres: the water was salty in the east at Texcoco and fresh in the south.
Practice question: To what extent did the environment of the Basin of Mexico shape the rise of Mexica power between 1325 and 1428?
5 more points of evidence, 3 primary sources and the model plan for this question are in the IB notes of chapter 7 in the atlas.
8. Water: Dikes, Aqueducts and Floods
CHAPTER 8 · 1428–1500 · CONCEPTS: CAUSATION, CONSEQUENCE, SIGNIFICANCE
EVIDENCE TO USE · 1 OF 6
- After the flood usually dated to 1449, Nezahualcoyotl designed a dike to protect the city. Workers from Tlacopan, Culhuacan, Iztapalapa, Tenayuca and Xochimilco built the stone, clay and stake barrier, which ran some 12–16 kilometres from Atzacoalco to Iztapalapa.
Practice question: How effective was Mexica hydraulic engineering in protecting Tenochtitlan from environmental hazards between 1428 and 1500?
5 more points of evidence, 4 primary sources and the model plan for this question are in the IB notes of chapter 8 in the atlas.
9. Chinampas: Feeding a City
CHAPTER 9 · c. 1430–1519 · CONCEPTS: CHANGE, SIGNIFICANCE, CONSEQUENCE
EVIDENCE TO USE · 1 OF 6
- Chinampas began as plots staked out in shallow fresh water. Farmers piled lake mud and vegetation inside them and anchored their edges with ahuejote willows, making moist, fertile beds that could carry several crops a year.
Practice question: Examine how important chinampas and the tribute system were in sustaining Tenochtitlan’s population.
5 more points of evidence, 4 primary sources and the model plan for this question are in the IB notes of chapter 9 in the atlas.
10. The Planned City
CHAPTER 10 · c. 1430–1519 · CONCEPTS: SIGNIFICANCE, PERSPECTIVES, CHANGE
EVIDENCE TO USE · 1 OF 6
- Tenochtitlan’s sacred precinct stood at the heart of the city and measured roughly 430–460 metres across. Sahagún’s informants listed 78 structures inside it; the twin shrines of the Templo Mayor, dedicated to Huitzilopochtli and Tlaloc, dominated the precinct.
Practice question: To what extent did Tenochtitlan’s plan solve environmental problems?
5 more points of evidence, 4 primary sources and the model plan for this question are in the IB notes of chapter 10 in the atlas.
11. The Flower Wars and the End of the System
CHAPTER 11 · 1450s–1521 · CONCEPTS: CAUSATION, CONSEQUENCE, PERSPECTIVES
EVIDENCE TO USE · 1 OF 6
- According to Alva Ixtlilxochitl, the Triple Alliance agreed in 1454 to fight Tlaxcala, Huexotzinco and Cholula in ritual flower wars to take captives. Ross Hassig interprets these wars as a form of attrition; Barry Isaac sees the ritual explanation as a cover for failure to conquer.
Practice question: To what extent was Indigenous opposition to the Mexica the main reason for the fall of Tenochtitlan in 1521?
5 more points of evidence, 4 primary sources and the model plan for this question are in the IB notes of chapter 11 in the atlas.
12. Two Answers to the Environment
EPILOGUE · c. 1450–1521 AND AFTER · CONCEPTS: CONTINUITY, CONSEQUENCE, SIGNIFICANCE
EVIDENCE TO USE · 1 OF 6
- At its height, Norse Greenland may have held 2,000–2,500 people. The Basin of Mexico may have held 1–1.5 million in 1519: a population several hundred times larger, with a different capacity to absorb climate shocks.
Practice question: Compare and contrast how the Norse in Greenland and the Mexica in the Basin of Mexico responded to the challenges of their environments.
5 more points of evidence, 4 primary sources and the model plan for this question are in the IB notes of chapter 12 in the atlas.
Practice questions and essay plans
Each chapter closes with a practice question and a model plan. The plan gives a thesis, three points with evidence and a link back to the question, a counter-argument and a judgement. Chapter 1’s plan appears here in full. The other plans are outlined here and given in full in the atlas.
PAPER 2 · CLIMATE AND INNOVATION · CHAPTER 1
How far was climate the main reason for the success and failure of medieval societies in demanding environments?
Climate changed the conditions in which these societies farmed and settled, but it rarely acted alone. Warm centuries opened the North Atlantic to Norse farming, and colder conditions narrowed that opportunity; frost and drought also struck the Mexica. Whether such pressures became a lasting catastrophe or a crisis survived depended on social structure, trade and technology.
Climate widened and then narrowed the margin for farming at the edge of the habitable world.
EVIDENCEScoop Lake midges suggest summers about 1.5 °C warmer in 900–1400, a period that includes the Norse settlement of Greenland in 985 or 986. Gifford Miller dates the onset of the Little Ice Age to 1275–1300, before the Western Settlement emptied.
LINKThe sequence makes climate a serious part of the explanation for expansion and retreat. Timing alone, however, cannot establish that cooling caused abandonment.
Communities facing colder conditions had different resources with which to respond.
EVIDENCEAfter 1300, Thule Inuit expanded down Greenland’s west coast while the Norse withdrew. Iceland, with perhaps 40,000–60,000 people, also survived the colder period.
LINKThe comparison directs attention to food, technology and scale. A broad climatic change could have different consequences for societies equipped to meet it in different ways.
Institutions could provide a buffer against shortage.
EVIDENCEMexica chronicles describe frost and drought in 1450–54, and tree rings independently indicate drought in 1452–54. Moctezuma I opened the royal granaries, and the rulers lifted tribute for six years. Greenland had no reserves and depended on one export, walrus ivory.
LINKGranaries and tribute policy could help a society survive famine. Greenland’s lack of reserves and reliance on a single export left it exposed to a different set of risks.
A climate-centred case remains strong. Dansgaard argued in 1975 that cooling had a major impact on Norse Greenland, while Zhao’s 2022 Lake 578 record points to drying that could have reduced hay yields. Hay failure alone, on this interpretation, could have made the colony unviable; human choices would then have changed the timing of withdrawal rather than its eventual outcome.
Climate set the margin within which these societies operated, and in Greenland that margin narrowed decisively. Yet the Inuit and Icelanders survived the colder period, and the Mexica survived drought. To explain those different outcomes, we must look at how local climatic pressures interacted with scale, trade, technology and institutions: these affected a society’s ability to absorb a bad decade.
Read the chapter behind this plan: Climate as a Force in History.
PAPER 2 · CLIMATE AND INNOVATION · CHAPTER 3
How did Norse settlement change Iceland’s environment and society between 870 and 1100?
Norse settlers created a mixed farming society and an island-wide assembly that governed without a king. Their woodcutting and grazing also changed the land on which that society depended. The institutions endured, while woodland loss and soil erosion continued long after the first generations of settlement.
Settlement brought a population with Norse and Gaelic roots.
The settlers’ farming practices changed the woods and soils.
The Althing gave a society without a king a means of making law and addressing disputes.
The evidence for each point, the counter-argument and the judgement are in the IB notes of chapter 3 in the atlas. Read the chapter first: Iceland: A Society on a Volcanic Island.
PAPER 2 · CLIMATE AND INNOVATION · CHAPTER 10
To what extent did Tenochtitlan’s plan solve environmental problems?
To a large extent, the city’s plan answered the difficulties of living densely on water: canals, causeway bridges, the aqueduct and waste arrangements all helped make that possible. But the sacred precinct, the alignment of the quarters and the successive rebuilding of the Templo Mayor show that religion and political power shaped the plan as strongly.
The street and canal grid made life on water workable.
A dense population depended on water supply and sanitation.
The city’s centre also expressed religion and power.
The evidence for each point, the counter-argument and the judgement are in the IB notes of chapter 10 in the atlas. Read the chapter first: The Planned City.
PAPER 2 · CLIMATE AND INNOVATION · CHAPTER 4
Compare and contrast the reasons for Norse settlement in Greenland with explanations for the abandonment of Vinland.
Both ventures belonged to a westward expansion in which people sought land during warm centuries. Their outcomes differed: Greenland combined pasture and a valuable export with relative proximity to Iceland, while Vinland was much farther from support and its visitors encountered numerous Indigenous inhabitants. We must also ask what the Norse intended their Vinland base to do.
The search for land carried Norse voyagers west during a warm period.
Greenland had an export with which to obtain imports.
Distance and encounters with Indigenous people mattered to Vinland’s short history.
The evidence for each point, the counter-argument and the judgement are in the IB notes of chapter 4 in the atlas. Read the chapter first: Greenland and Vinland.
Primary sources
Before reading a primary source, it helps to know where it came from and its context. Each chapter’s IB notes provide both. Here are the sources from chapter 1 in full.
PICTURE · CHAPTER 1
Central Greenland temperature, AD 700–1700, from the GISP2 ice core
- CREATOR
- Maps of History, from data published by R.B. Alley
- DATE
- 2000 (data); 2026 (chart)
- ORIGIN
- Line chart drawn from the GISP2 temperature reconstruction (NOAA/NCEI paleoclimate study 2475), with dates of Norse settlement and abandonment added
Context. The smoothed series uses the oxygen isotope composition of snow at the ice-sheet summit, about 3,200 metres above sea level. The underlying series ends in 1855; summit conditions are not a direct measurement of coastal farms.
Chart: Maps of History. Data: Alley, R.B. 2000, Quaternary Science Reviews 19: 213–226; NOAA/NCEI study 2475. · original ↗
PICTURE · CHAPTER 1
Drought and wet years in central Mexico, 1300–1600, from tree rings
- CREATOR
- Maps of History, from data published by D.W. Stahle and colleagues
- DATE
- 2011 (data); 2026 (chart)
- ORIGIN
- Bar chart drawn from the Mesoamerican June soil-moisture reconstruction (NOAA/NCEI study 11175), based on Montezuma baldcypress trees at Barranca de Amealco, Querétaro
Context. These trees grew about 130 km northwest of the Basin of Mexico. The regional Mexican Drought Atlas of 2016 shows the 1452–54 drought more strongly than this single-site record.
Chart: Maps of History. Data: Stahle, D.W. et al. 2011, Geophysical Research Letters 38: L05703; NOAA/NCEI study 11175. · original ↗
PICTURE · CHAPTER 1
The opening of the Saga of the Greenlanders in Flateyjarbók
- CREATOR
- Scribes Jón Þórðarson and Magnús Þórhallsson
- DATE
- 1387–1394
- ORIGIN
- Manuscript page, GKS 1005 fol., Árni Magnússon Institute for Icelandic Studies, Reykjavík
Context. The saga describes voyages to Greenland and Vinland, but this manuscript was written in Iceland almost four centuries after them.
Flateyjarbók, GKS 1005 fol., Árni Magnússon Institute; image via Wikimedia Commons (public domain). · original ↗
TEXT · CHAPTER 1
The King’s Mirror on the ice around Greenland
- CREATOR
- Anonymous Norwegian author
- DATE
- c. 1250
- ORIGIN
- Konungs skuggsjá (The King’s Mirror), a book of instruction written as a dialogue between a father and son, ch. XVI
Context. The anonymous author wrote in Norway around 1250 and drew on reports from sailors and merchants who had visited Greenland.
Translation: L.M. Larson, The King’s Mirror (New York: American-Scandinavian Foundation, 1917), pp. 138–139. · original ↗
Every other source in the atlas (42)
- Chapter 2: The Ship and the Sea Road
- The Anglo-Saxon Chronicle on the raid on Lindisfarne Anonymous monastic chroniclers · Entry for 793 (compiled from the late ninth century)
- Alcuin to King Æthelred of Northumbria Alcuin of York · 793
- Ohthere’s account of walrus hunting Ohthere of Hålogaland, recorded at the court of King Alfred · c. 890
- The Gokstad ship Norwegian shipbuilders; photograph by Daderot · Ship built c. 890; photograph 2009
- Chapter 3: Iceland: A Society on a Volcanic Island
- Íslendingabók on the first settler and the wooded land Ari Þorgilsson · 1122–1133
- Íslendingabók on the founding of the Althing Ari Þorgilsson · 1122–1133
- The Law Rock at Þingvellir Photograph by Gerd Eichmann · 2018
- Landnámabók’s sailing directions to Greenland Haukr Erlendsson (compiler of the Hauksbók version) · Early fourteenth century, from older material
- Chapter 4: Greenland and Vinland
- Erik the Red’s Saga on naming Greenland Anonymous Icelandic author · Thirteenth century
- The Saga of the Greenlanders on Leif’s winter in Vinland Anonymous Icelandic author · Thirteenth century (copied in Flateyjarbók, 1387–94)
- The Saga of the Greenlanders on trade with the Skrælings Anonymous Icelandic author · Thirteenth century (copied in Flateyjarbók, 1387–94)
- Reconstructed Norse buildings at L’Anse aux Meadows Photograph by Eric Titcombe · 2013 (reconstructions built by Parks Canada)
- Chapter 5: Living with the Cold
- Ivar Bárðarson’s description of the old sailing route to Greenland Attributed to Ivar Bárðarson, steward at Garðar · Mid-fourteenth century (surviving in later Danish copies)
- Ivar Bárðarson on the Western Settlement found empty Attributed to Ivar Bárðarson, steward at Garðar · Mid-fourteenth century (surviving in later Danish copies)
- Icelandic annals on Greenland, 1347 and 1379 Icelandic annalists · Entries for 1347 and 1379 (manuscripts of the fourteenth to sixteenth centuries)
- The ruin of Hvalsey church, Greenland Norse builders; photograph by Number 57 · Church built probably in the fourteenth century; photograph uploaded 2014
- Chapter 6: What the Norse Left
- The King’s Mirror on Greenland’s imports and exports Anonymous Norwegian author · c. 1250
- The Lewis chessmen Unknown carvers, probably in Trondheim; photograph by Naddoddr · Carved c. 1150–1200; photograph 2025
- The Skálholt map of the North Atlantic Sigurður Stefánsson (original, lost); copied for Þórður Þorláksson · Original c. 1570; surviving copy 1669
- Chapter 7: An Empire Built on a Lake
- The founding of Tenochtitlan in the Codex Mendoza Unknown Nahua painter-scribe (tlacuilo) · c. 1541–42
- Cortés on the lakes and the island city Hernán Cortés · 30 October 1520
- A lament attributed to Nezahualcoyotl Attributed to Nezahualcoyotl, ruler of Texcoco (1402–72) · Fifteenth century (written down in Spanish in the early seventeenth century)
- Chapter 8: Water: Dikes, Aqueducts and Floods
- Torquemada on the building of the dike Juan de Torquemada, Franciscan friar · Published 1615 (this edition 1723)
- Nezahualcoyotl’s dike on the 1524 Nuremberg map Unknown draughtsman; woodcut printed by Friedrich Peypus · 1524
- Alva Ixtlilxochitl on the snow of 1450 and the famine that followed Fernando de Alva Ixtlilxochitl, historian descended from the rulers of Texcoco · c. 1610–40
- Durán on the Acuecuexco flood of 1499 Diego Durán, Dominican friar · c. 1581
- Chapter 9: Chinampas: Feeding a City
- The tribute of Tochtepec in the Codex Mendoza Unknown Nahua painter-scribe (tlacuilo) · c. 1541–42
- Grain bins in the Codex Mendoza Unknown Nahua painter-scribe (tlacuilo) · c. 1541–42
- Cortés on the great market Hernán Cortés · 30 October 1520
- Bernal Díaz on the market of Tlatelolco Bernal Díaz del Castillo, soldier with Cortés · Written c. 1550s–1570s (published 1632)
- Chapter 10: The Planned City
- Bernal Díaz on the first sight of the lake cities Bernal Díaz del Castillo, soldier with Cortés · Written c. 1550s–1570s (published 1632)
- Bernal Díaz on the view from the great temple Bernal Díaz del Castillo, soldier with Cortés · Written c. 1550s–1570s (published 1632)
- Cortés on the aqueduct and the water supply Hernán Cortés · 30 October 1520
- The 1524 Nuremberg map of Tenochtitlan Unknown draughtsman; woodcut printed by Friedrich Peypus · 1524
- Chapter 11: The Flower Wars and the End of the System
- Sahagún on the smallpox epidemic of 1520 Bernardino de Sahagún, Franciscan friar, with Nahua informants · Compiled c. 1555–1577
- Smallpox in the Florentine Codex Nahua artists working with Bernardino de Sahagún · c. 1575–77
- Cortés on cutting the aqueduct and the hunger in the city Hernán Cortés · 15 May 1522
- Tlaxcalan warriors and their Spanish allies in the Lienzo de Tlaxcala Tlaxcalan painters; later copy of the lost original · Original c. 1550s
- Chapter 12: Two Answers to the Environment
- An Inuit tradition of the first meeting with the Norse Greenlandic storytellers, recorded and translated by Hinrich Rink · Recorded in the nineteenth century; published 1875
- Thule-culture snow goggles Thule-culture maker, Alaska · c. 800–1200
- Model of chinampas in the Templo Mayor Museum Museum model; photograph by Thelmadatter · Photograph 2008
- The Templo Mayor ruins and the cathedral of Mexico City Photograph by Thelmadatter · 2008
Internal Assessment starting points
Each starting point is an idea for an investigation: a question, the concept it tests, the kinds of sources you could use and where they are held, and one caution. The investigation must be your own work, and your teacher approves the question.
How far do ice cores and lake sediments support Icelandic annals describing cooler conditions in Norse Greenland, 1250–1450?
CONCEPTCausation
SOURCESPublished proxy data (GISP2 temperature series, lake-sediment studies), translated Icelandic annals and the description attributed to Ivar Bárðarson.
CAUTIONBefore comparing a proxy with an annal, establish where it was measured and what it records. An ice core from the summit and a coastal lake record different conditions.
How reliable are the two Vinland sagas as accounts of Norse encounters with Indigenous peoples in North America?
CONCEPTPerspectives
SOURCESThe Saga of the Greenlanders and Erik the Red’s Saga in translation, excavation reports from L’Anse aux Meadows and the 2021 tree-ring dating.
CAUTIONBoth sagas were written down centuries after the events and present Norse perspectives. Archaeology adds another kind of evidence, though it cannot directly recover every Indigenous viewpoint.
What can the Codex Mendoza establish about the scale of Mexica tribute?
CONCEPTSignificance
SOURCESThe tribute pages of the Codex Mendoza, their Spanish annotations and modern commentaries.
CAUTIONMade for Spanish officials about twenty years after the conquest, the codex records quantities whose meaning and frequency remain contested. Those uncertainties matter when estimating tribute’s scale.
Why was Nezahualcoyotl’s dike built, and how well did it work?
CONCEPTConsequence
SOURCESChronicles by Torquemada, Durán and Alvarado Tezozómoc, the 1524 Nuremberg map and modern archaeological surveys of the lake bed.
CAUTIONThe chroniclers wrote later and often drew on shared sources. When they agree, their accounts may preserve one tradition rather than independent testimony.
How important was the 1520 smallpox epidemic to the fall of Tenochtitlan?
CONCEPTCausation
SOURCESBook XII of the Florentine Codex, Cortés’s letters, Indigenous annals and modern demographic studies.
CAUTIONMortality estimates depend on uncertain population figures. For each estimate, identify its source, date and range before using it.
How far did changes in trade, compared with climate, contribute to the abandonment of Norse Greenland?
CONCEPTCausation
SOURCESAncient-DNA studies of walrus ivory, the King’s Mirror, Icelandic annals and archaeological reports on Greenland farms.
CAUTIONTrade and climate may have changed at similar times without one change causing the other. Read the statistical studies in context and distinguish timing from evidence of causation.
How much continuity is there between Xochimilco’s chinampa farming before 1521 and today?
CONCEPTContinuity
SOURCESColonial land records, travellers’ accounts, the UNESCO nomination file and modern agricultural studies.
CAUTIONCompare evidence from several dates: the crops, water supplies and uses of modern chinampas differ from those of 1519.
Revision tools
The atlas ends with a map quiz that asks you to find places and moments on the map itself (part of every plan from Starter up). The quick quiz and the discussion questions with our answers are free pages on this site, and the printable study guide gathers every chapter’s notes into one document for revision.
Maps of History is independent and is not affiliated with or endorsed by the International Baccalaureate Organization. IB course names describe alignment only; paper, theme and section names follow the new course outline and may change when the final guide is published.
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