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View series: The United States: a territorial history

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Reconstruction and the End of the “Frontier”

This map is part of a series of 20 animated maps showing the history of The United States: a territorial history.

After 4 years of civil war, the Union finally forced the Confederate States to surrender. However, the arrival of peace between the warring factions opened up a new period of controversy over reconstruction of the nation’s unity, during which the southern States sought to avoid granting civil and political rights to freed slaves and to develop a society based on racial segregation.

Tennessee was readmitted to the Union in 1866.

However, the passing of the Reconstruction Laws of 1867 placed the other Confederate States under military government in order to ensure law and order and to monitor electoral rolls.

Authorization to send representatives to Congress was granted to the Southern States in several phases:

The first six by late 1868: Arkansas, Alabama, Florida, Louisiana, South Carolina and North Carolina.

The remaining four states were readmitted in 1870: Mississippi, Texas, Virginia and Georgia.

The 25 years following the Civil War was a time of substantial economic prosperity. Industry benefited from a strong boom period and gradually began to dominate the economy, pushing agriculture into second position.

The North attracted a growing number of immigrants, more than 1 million in some years. This new source of labour, together with strong demographic growth, led to spectacular urban development.

In the west, the construction of transcontinental railroads and the adoption of the Homestead Act facilitated new development in the Great Plains, the Rockies and the Pacific regions. This law offered settlers plots of 64 hectares free of charge in order to set themselves up as farmers.

By the end of the century, the Conquest of the West was complete and the line that defined the frontier of the inhabited world, no longer existed.

With the transformation of the western territories, several new states were admitted to the Union:

Nevada in1864

Nebraska in 1867

Colorado in 1876

The States of Washington, Montana and North and South Dakota in 1889

Wyoming and Idaho in 1890

Because of the Mormon practice of polygamy, which was prohibited under Federal law, the admission of Utah was delayed until 1896.

Several years later, it was Oklahoma’s turn to be admitted, after long years as a territory reserved for Indians, followed by Arizona and New Mexico in 1912

Two territories separated geographically from the United States, Alaska and Hawaii, were acquired during the second half of the 19th century and became the 49th and 50th States of the Union in 1959.