1821

independence of Mexico

1835

second Seminole war in Florida (1835-1842)

1836

independence of Texas

1838

forced relocation of the eastern tribes also known as the Trail of Tears (1838-1839)

1845

U.S. annexation of Texas

1846

Mexican war (1846-1848)

1846

military actions in California (Bear Flag Revolt)

1847

Mormon relocation (opening of the Utah Trail)

1847

Mexican defeat

1848

peace treaty with Mexico (Treaty of Guadalupe Hidalgo)

1849

discovery of gold in California (Gold Rush)

1851

first Laramie Treaty

1855

third Seminole war in Florida (1855-1858)

1857

Mormon or Utah war

1859

discovery of gold in Colorado

1861

start of the American Civil War (1861-1865)

1862

bloody Santee Sioux uprising in Minnesota

1864

Navajo war in Arizona (Kit Carson)

1864

pointless butchery of peacfull Cheyenne village in Colorado (Sand Creek Massacre)

1865

end of the Civil War, assassination of President Lincoln

1866

annihilation of American troops by a large Sioux war party in Wyoming (Fetterman Massacre)

1867

military government of the "rebel states"

1867

the Alaska purchase

1868

massacre of a Cheyenne village by an American expeditionary force in Oklahoma (Washita)

1868

second Laramie Treaty

1869

first transcontinental railway operational (Golden Spike, Utah)

1871

Southern Prairie Indian war (1871-1875)

1872

first National Park : Yellowstone

1872

Modoc Indian war in Califora (1872-1873)

1873

Northern Prairie Indian war (1873-1877)