MTMontana History

Montana at a historical glance

Montana was admitted to the Union on 1889, making it the 39th state. It joined the country 113 years after the Declaration of Independence. Its capital Helena has been the seat of state government for most of the state's history. The state's history reflects waves of migration, conflict, and adaptation — from Indigenous civilizations through European colonization, statehood, the Civil War era, industrialization, civil rights, and the modern era.

Native peoples (pre-1500s)

For at least 10,000 years before European contact, Indigenous peoples lived across what is now Montana. Multiple distinct cultures developed in response to the region's geography — coastal peoples, plains peoples, river-valley peoples, mountain peoples — each with their own languages, governance, trade networks, religious practices, and agricultural traditions. Major Native nations in the region developed sophisticated political structures, sometimes spanning territory larger than entire modern states.

European colonization disrupted these civilizations dramatically. Disease (particularly smallpox, to which Native peoples had no immunity) wiped out an estimated 70-90% of Indigenous populations within 100 years of European arrival. Forced displacement, broken treaties, and the Indian Removal Act of 1830 further reshaped Native presence in the region. Today, Montana's Native heritage is preserved in place names (cities, rivers, counties), tribal nations within state borders, ongoing cultural practices, and an active sovereignty movement.

French colonial era

French explorers and fur traders moved through the region as early as the 17th century. French influence is visible in place names, the Catholic religious traditions, and (where applicable) Cajun or Creole cultures. France controlled vast portions of central North America before losing the territory to Spain in 1762, then back to France briefly, then to the United States via the 1803 Louisiana Purchase. Even after losing political control, French cultural influence persisted — particularly in Louisiana and parts of the upper Midwest.

The Louisiana Purchase (1803)

Montana was part of the territory the United States acquired from France in 1803 for $15 million — roughly $0.03 per acre — the Louisiana Purchase. It doubled the size of the United States overnight, transferred approximately 828,000 square miles to American control, and set in motion decades of westward exploration and settlement. The Lewis and Clark Expedition (1804-1806) was directly funded by Congress to map the new territory.

The purchase was constitutionally controversial — the Constitution didn't explicitly grant the President power to buy foreign territory. Thomas Jefferson, who orchestrated the deal, privately questioned its legality but proceeded anyway. The Supreme Court has since upheld treaty-based territorial acquisition.

The 19th century in Montana

The 19th century was a period of dramatic change for Montana. Westward expansion, industrialization, immigration waves, railroad construction, the Civil War, Reconstruction, and the closing of the American frontier all shaped the state's development. Population grew steadily — sometimes through internal migration, sometimes through international immigration. The agrarian economy gave way (in many states) to industrial and urban economies. State governments expanded their roles: public education systems, infrastructure, public health, and (eventually) regulation of business all emerged in this era.

The 20th century

The 20th century brought two World Wars, the Great Depression, the New Deal, the Civil Rights Movement, the Cold War, the Space Race, the women's rights movement, and the rise of mass consumer culture. Montana participated in all of these in ways shaped by its local geography, demographics, and economy. Military bases, defense industries, federal investment in infrastructure (Interstate Highway System, dams, airports), and the GI Bill (which subsidized college education for veterans) all reshaped the state in the postwar era.

The modern era and demographics today

Today Montana has a population of 1 to 5 million and is one of the largest states. The capital is Helena; the largest city is Billings. The economy benefits significantly from oil and natural gas production. Agriculture remains an important sector. Tourism is a major economic driver. Political alignment has shifted over time and currently leans reliably Republican.

Historical sites and museums

Montana preserves its history through state parks, national monuments, historic districts, museums, and battlefields. The state historical society maintains records and offers educational programs. For a complete list of historic sites, visit the state's official tourism site or the National Park Service.

Montana notable firsts

• Contains part of Yellowstone, the world's first national park (1872)

Montana vs similar states

How does Montana compare with 3 other states in the same region and size category?

State	Capital	Pop	Area rank	Admitted
Montana	Helena	1 to 5 million	#4	1889
Alaska	Juneau	under 1 million	#1	1959
Arizona	Phoenix	5 to 10 million	#6	1912
California	Sacramento	over 10 million	#3	1850

Bordering states (4)

Montana shares borders with 4 other US states, listed alphabetically below. Each link goes to the dedicated state page.

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