The American Civil War, 1840–1877 · THE MAP IN DEC 1845

Map of the United States in December 1845

Texas annexed

The United States in December 1845: Texas annexed. The map shows who held what: The Union, Mexico, 1840–54.

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Map of the United States in December 1845: Texas annexed. Colours show The Union, Mexico, 1840–54. — DEC 1845 · THE AMERICAN CIVIL WAR, 1840–1877

These maps are reconstructed from published sources · Cliopatria v 0.2.1 · Treaty of Guadalupe Hidalgo, 1848 · US Military Academy: Summary of Operations, 1846-47 · Newberry Atlas of Historical County Boundaries: historical states and territories · Maps of History: Civil War source decisions

Source details

Cliopatria contributors / Seshat Global History Databank. Selected, combined, reprojected and corrected by Maps of History as described per layer.. CC BY4.0
US National Archives, treaty and territorial cession.. Historical treaty evidence
US Military Academy Department of History; selected geographic facts reconstructed independently, original chart retained outside distributed files.. Geographic evidence only. Source atlas index requests reprint permission; original artwork not redistributed.
The Newberry Library, Atlas of Historical County Boundaries. State/territory records unioned for the displayed date; disputed/joint territories excluded from exclusive US sovereignty.. Publisher permits commercial and noncommercial lawful reuse without fees; current terms supersede obsolete NC notice in archive
Source-native legal boundaries, annual military control and independently reconstructed campaign sectors are kept separate. Region connectors and corridor widths are interpretive.. Original historical reconstruction with attributed evidence

Legal US boundaries come from dated Newberry records. Secession and military control use separate source layers, while campaign corridors are educational geographic reconstructions rather than surveyed continuous fronts.

reconstruction: 1840 · reconstruction: 1840-07-01 · reconstruction: 1845 · vector: 1860 state-interface reference · vector: us-7c228f25e0d8

Layer records and reconstruction methods

On the ground

California and New Mexico lay in Mexico’s far north. Polk offered to buy them in 1845, but Mexico refused to sell.

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