List of U.S. states by date of admission to the Union

List of U.S. states by date of admission to the Union details the chronological order in which each state joined the United States of America. The process is governed by Article IV of the U.S. Constitution and typically follows a period of territorial governance. This list begins with the original Thirteen Colonies that ratified the Constitution in the late 18th century and extends to the admission of Hawaii in the mid-20th century.

List of states in order of admission

The first states were the original thirteen colonies, with Delaware leading by ratifying the Constitution on December 7, 1787. Pennsylvania and New Jersey followed within days, with the final original state, Rhode Island, joining in May 1790. The next major phase occurred with the admission of Vermont in 1791, followed by Kentucky in 1792 and Tennessee in 1796 from the trans-Appalachian frontier. The early 19th century saw the admission of states carved from the Louisiana Purchase, such as Louisiana (1812) and Missouri (1821). The Mexican–American War and subsequent Treaty of Guadalupe Hidalgo facilitated the admission of California in 1850. Post-Civil War admissions included Nebraska (1867) and Colorado (1876). The last contiguous states, Arizona and New Mexico, were admitted in 1912, while the non-contiguous states of Alaska and Hawaii joined in 1959.

Background on statehood process

The path to statehood is outlined in the Northwest Ordinance of 1787 and Article IV, Section 3 of the Constitution. Typically, a territory petitions Congress, which then passes an enabling act authorizing the drafting of a state constitution. Following a successful referendum and congressional approval of that constitution, Congress passes a joint resolution for admission, which is signed by the President. Key congressional figures in statehood debates have included Henry Clay and Stephen A. Douglas. The Department of the Interior often oversees territorial affairs. The final step is a presidential proclamation, as issued by Dwight D. Eisenhower for Alaska and Hawaii.

Historical context and territorial evolution

Statehood admissions often mirrored the nation's geographic and political expansion. The Louisiana Purchase (1803) provided the land for multiple future states, including Arkansas and Iowa. The Adams–Onís Treaty secured Florida, which became a state in 1845. The concept of Manifest Destiny drove westward expansion, leading to the annexation of the Republic of Texas in 1845 and the acquisition of the Oregon Territory via the Oregon Treaty with Great Britain. The Mexican–American War concluded with the Treaty of Guadalupe Hidalgo, ceding the Mexican Cession that formed the basis for states like Nevada and Utah. The Gadsden Purchase finalized the southern borders of Arizona and New Mexico. The Alaska Purchase from Russia and the annexation of the Kingdom of Hawaii set the stage for the final two states.

Related lists and tables

Several other enumerations provide complementary perspectives on the states. The list by population shows demographic shifts since admission. The list by area highlights the vast territories acquired through purchases and treaties. The list of state capitals details seats of government, many of which were established prior to statehood. Historical political alignment can be traced through the list of states and the order of admission, which often influenced their stance during events like the Civil War. The Thirteen Colonies have their own distinct historical catalogs.

Notes on the list

Several states have unique admission circumstances. West Virginia was created from Virginia during the Civil War via the Wheeling Convention and admitted in 1863. Maine was separated from Massachusetts via the Missouri Compromise of 1820. The status of Texas is unique as it was an independent republic before annexation. The dates for the original thirteen states refer to their ratification of the Constitution, not their founding as colonies. Disputes, such as the Toledo War between Michigan and Ohio, occasionally delayed admissions. The most recent state, Hawaii, was admitted following a popular referendum and the Hawaii Admission Act.

Category:Lists of U.S. states by date of admission to the Union States by date of admission to the Union