Map of pre-colonial Africa, showing the predominately native countries and territories of the African continent in 1879. The counties include the Barbary States of Morocco, Algeria, Tunis, Tripoli and Fezzan, the Egyptian territories of...

A map of the western United States and northern Mexico showing the territorial disputes settled and boundary established by the Adams-Onis Treaty between the United States and Spain in 1819. The territorial disputes involved the natural...

A map of the United States showing the principal trade and westward migration routes between 1840 and 1850. The map shows state and territory boundaries at the time, major cities, ports, outposts, forts, and settlements, rivers, mountain...

A map of the American Northwest Territory showing the boundary developments in 1790, 1800, and 1810. The upper left map shows the territory acquired by the United States from Britain after the Revolutionary War as established by the...

A map of the Oregon Territory showing the boundary on the 49th Parallel established by treaty between Great Britain and the United States in 1846, dividing what was once jointly held territory. The map also shows the boundary with Upper...

A map of the United States showing the extent of the country prior to, and after the Louisiana Purchase from France in 1803.

A map of the United States and territories showing the expansion from the formation of the original states to the purchase of the Danish West Indies (Virgin Islands) in 1917. The map is color-coded to show the original states, the states...

A map of territory claimed by Texas when admitted into the Union in 1845. The map is coded to show the frontiers of Texas with the United States and Mexico, and the disputed territory in the west between the Rio Grande and Nueces rivers.

A map of the United States in 1840, showing the frontier line, indicate by the thick black line.

A map of the United States in 1850, showing the frontier line, indicate by the thick black line. The map shows the States added to the Union between 1840 and 1850, including Florida (1845), Texas (1845), Iowa (1846), Wisconsin (1848),...

A map of the Louisiana territory purchased from France in 1803, and the boundary established with the western Spanish territory by the purchase.

A map of the Oregon Country showing the adjustments to the boundaries between 1819-1846, including the southern boundary established by treaty with Spain in 1819, and the boundary dividing the territory between the United States and...

A map of the Louisiana territory purchased from France in 1803, and the boundary established with the western Spanish territory by the purchase. The map overlays the current State boundaries to show the extent of the territory.

A map of territory claimed by Texas when admitted into the Union, 1845. The map is color-coded to show the frontiers of Texas with the United States and Mexico, the territory in the east covered under the old Spanish land grants, and the...

A map of long Distance Routes from St. Louis to Denver.

A map of the central and eastern United States in 1860 showing the distribution of the population in the region at the time. The map shows State lines, the frontier line in 1860, and is keyed to show the areas of population density...

A map of the United States showing the population distribution in 1850. The map is coded to show population densities ranging from under 2 inhabitants per square mile to over 90 inhabitants per square mile. The map illustrates the...

A map of the United States and territories showing the westward expansion after the Missouri Compromise (1820) and the admission of Missouri into the Union in 1821.

A map of the Perdido River area, including Mobile Bay, Pensacola, and the Mississippi Delta. The Perdido River was the disputed boundary of West Florida between the United States and Spain, resolved in 1819 when Spain ceded Florida under...

A map of the United States in 1861 after the secession of the Southern States. The map is color-coded to show the Free Union States, Union Slaveholding States, Confederate States, and the territories of Washington, Dakota, Nevada, Utah,...

A map of the Oregon Country showing the adjustments to the boundaries between 1818-1846, including the boundary established in 1818 to the east of the jointly controlled territory (Great Britain and the United States), the southern...

A map of the United States and territories showing the free areas and areas open to slavery as established by the Missouri Compromise of 1820.

A map of the United States and territories showing the expansion from the formation of the original states to 1880, and the railroad network in 1880. The map is color-coded to show the original states, the states admitted between 1791...

A map of the central and eastern United States in 1840 showing the distribution of the population in the region at the time. The map shows State lines, the frontier line in 1840, and is keyed to show the areas of population density...