This timeline is a chronology of significant events in the history of the U.S. State of Montana and the historical area now occupied by the state. __NOTOC__

2020s YearDateEvent2024November 5The 2024 General Election will be held on November 5, 2024.2022November 8In the 2022 general election, Montana voters elect Ryan Zinke as the U.S. representative for the new 1st congressional district and U.S. representative at-large Matt Rosendale for the new 2nd Congressional District. Republicans retain control of the Montana Legislature.2020November 3In the 2020 General Election, Montana voters elect three presidential electors for Donald Trump, re-elect Steve Daines as junior U.S. Senator, elect Matt Rosendale as U.S. representative at-large, and elect Greg Gianforte as Governor. Republicans retain control of the Montana Legislature.April 1The 2020 United States census enumerates the population of the State of Montana, later determined to be 1,084,225, an increase of 9.58% since the 2010 United States census. Montana remains the 44th most populous of the 50 U.S. states, but will gain a second Congressional seat.

2010s YearDateEvent2019December 2Governor Steve Bullock announces the end of his campaign for President of the United States.January 7Governor Steve Bullock announces his candidacy for President of the United States.2018December 15Ryan Zinke resigns as United States Secretary of the Interior following congressional investigations.November 6In the 2018 General Election, Montana voters re-elect Jon Tester as senior U.S. Senator and elect Greg Gianforte as U.S. representative at-large. Republicans retain control of the Montana Legislature.October 18At a political rally in Missoula, U.S. President Donald Trump congratulates Congressman Greg Gianforte for his assault of reporter Ben Jacobs.2017May 25In the special congressional replacement election, Montana voters elect Greg Gianforte U.S. representative at-large.May 24Congressional candidate Greg Gianforte assaults reporter Ben Jacobs.March 1U.S. representative at-large Ryan Zinke is confirmed and assumes office as United States Secretary of the Interior.2016November 8In the 2016 general election, Montana voters elect three presidential electors for Donald Trump, re-elect Ryan Zinke as U.S. representative at-large, and re-elect Steve Bullock as Governor. Republicans retain control of the Montana Legislature.2015January 3Steve Daines assumes office as the junior United States senator for the State of Montana.2014November 4In the 2014 General Election, Montana voters elect Steve Daines as junior U.S. Senator and elect Ryan Zinke as U.S. representative at-large. Republicans retain control of the Montana Legislature.2013January 7Steve Bullock assumes office as the 24th governor of the State of Montana.2012November 6In the 2012 general election, Montana voters elect three presidential electors for Mitt Romney, re-elect Jon Tester as senior U.S. Senator, elect Steve Daines as U.S. representative at-large, and elect Steve Bullock as governor. Republicans retain control of the Montana Legislature.2010November 2In the 2010 general election, Montana voters re-elect Denny Rehberg as U.S. representative at-large. Republicans retain control of the Montana Senate and regain control of the Montana House of Representatives.April 1The 2010 United States census enumerates the population of the State of Montana, later determined to be 989,415, an increase of 9.7% since the 2000 United States census. Montana remains the 44th most populous of the 50 U.S. states.

2000s YearDateEvent2009March 30U.S. President Barack Obama signs An Act to designate certain land as components of the National Wilderness Preservation System, to authorize certain programs and activities in the Department of the Interior and the Department of Agriculture, and for other purposes, creating the Pacific Northwest National Scenic Trail and the Ice Age Floods National Geologic Trail.2007January 3Jon Tester assumes office as the junior United States senator for the State of Montana.2005January 3Brian Schweitzer assumes office as the 23rd Governor of the State of Montana.2001January 17U.S. President Bill Clinton issues an executive orders creating Pompeys Pillar National Monument and Upper Missouri River Breaks National Monument.January 1Judy Martz assumes office as the 22nd Governor of the State of Montana.2000April 1The 2000 United States census enumerates the population of the State of Montana, later determined to be 902,195, an increase of 12.9% since the 1990 United States census. Montana remains the 44th most populous of the 50 U.S. states.

1990s YearDateEvent1995December 9The United Nations Educational, Scientific and Cultural Organization (UNESCO) designates Waterton-Glacier International Peace Park as a World Heritage Site.1993January 4Marc Racicot assumes office as the 21st Governor of the State of Montana.1992October 30U.S. President George H. W. Bush signs An Act to amend the Act of May 15, 1965, authorizing the Secretary of the Interior to designate the Nez Perce National Historical Park in the State of Idaho, and for other purposes. The Nez Perce National Historical Park now includes the Big Hole National Battlefield and the Bear Paw Battlefield in Montana.1991December 10U.S. President George H. W. Bush signs An Act of Congress changing the name of the Custer Battlefield National Monument to the Little Bighorn Battlefield National Monument.1990April 1The 1990 United States census enumerates the population of the State of Montana, later determined to be 786,690, an increase of 1.6% since the 1980 United States census. Montana remains the 44th most populous of the 50 U.S. states, but will lose its 2nd Congressional District.

1980s YearDateEvent1989January 2Stan Stephens assumes office as the 20th Governor of the State of Montana.1986October 6U.S. President Ronald Reagan signs An Act to amend the National Trails System Act by designating the Nez Perce (Nee-Me-Poo) Trail as a component of the National Trails System, creating the Nez Perce National Historic Trail.1981January 5Ted Schwinden assumes office as the 19th Governor of the State of Montana.1980April 1The 1980 United States census enumerates the population of the State of Montana, later determined to be 786,690, an increase of 13.3% since the 1970 United States census. Montana becomes the 44th most populous of the 50 U.S. states.

1970s YearDateEvent1978November 10U.S. President Jimmy Carter signs the National Parks and Recreation Act of 1978 authorizing the Lewis and Clark National Historic Trail and the Continental Divide National Scenic Trail.October 9The United Nations Educational, Scientific and Cultural Organization (UNESCO) designates Yellowstone National Park as one of the first 12 World Heritage Sites.1976July 4The State of Montana celebrates the Bicentennial of the United States of America.1973January 1Thomas Lee Judge assumes office as the 18th Governor of the State of Montana.1972August 25U.S. President Richard Nixon signs An Act to authorize the establishment of the Grant Kohrs Ranch National Historic Site in the State of Montana, and for other purposes.1970April 1The 1970 United States census enumerates the population of the State of Montana, later determined to be 694,409, an increase of 2.9% since the 1960 United States census. Montana becomes the 43rd most populous of the 50 U.S. states.

1960s YearDateEvent1969January 6Forrest H. Anderson assumes office as the 17th Governor of the State of Montana.1968December 2U.S. President Lyndon B. Johnson signs An Act to establish a national trails system, and for other purposes, creating the National Trails System.1966October 15U.S. President Lyndon B. Johnson signs An Act to provide for the establishment of the Bighorn Canyon National Recreation Area, and for other purposes.June 20The National Park Service establishes Fort Union Trading Post National Historic Site.1965July 1The State of Montana changes the name of the Agricultural College of the State of Montana to Montana State University.1963May 17U.S. President John F. Kennedy signs An Act to redesignate the Big Hole Battlefield National Monument, to revise the boundaries thereof, and for other purposes, changing the name of Big Hole Battlefield National Monument to Big Hole National Battlefield.1962January 25Lieutenant Governor Tim Babcock assumes office as the 16th Governor of the State of Montana1961January 2Donald Grant Nutter assumes office as the 15th Governor of the State of Montana.1960April 1The 1960 United States census enumerates the population of the State of Montana, later determined to be 674,767, an increase of 14.2% since the 1950 United States census. Montana becomes the 41st most populous of the 50 U.S. states.

1950s YearDateEvent1953January 5J. Hugo Aronson assumes office as the 14th Governor of the State of Montana.1950April 1The 1950 United States census enumerates the population of the State of Montana, later determined to be 591,024, an increase of 5.6% since the 1940 United States census. Montana becomes the 42nd most populous of the 48 U.S. states.

1940s YearDateEvent1949January 3John W. Bonner assumes office as the 13th Governor of the State of Montana.1946March 22Custer Battlefield National Monument.1945September 2World War II ends as the Empire of Japan formally surrenders.May 8The war in Europe ends as the Greater German Empire formally surrenders.1941December 11The United States declares war on the German Reich and the Italian Empire.December 8The United States declares war on the Empire of Japan and enters World War II.January 6Sam C. Ford assumes office as the 12th Governor of the State of Montana.1940April 1The 1940 United States census enumerates the population of the State of Montana, later determined to be 559,456, an increase of 4.1% since the 1930 United States census. Montana remains the 39th most populous of the 48 U.S. states.

1930s YearDateEvent1937August 24U.S. President Franklin D. Roosevelt signs An Act authorizing the Secretary of the Interior to convey certain land to the State of Montana to be used for the purposes of a public park and recreational site, transferring Lewis and Clark Cavern National Monument to the State of Montana to become Lewis and Clark Caverns State Park.July 22U.S. President Franklin D. Roosevelt signs An Act to create the Farmers' Home Corporation, to promote more secure occupancy of farms and farm homes, to correct the economic instability resulting from some present forms of farm tenancy, and for other purposes, also known as the Bankhead-Jones Farm Tenant Act.January 4Roy E. Ayers assumes office as the 11th Governor of the State of Montana.1935December 15President of the Montana Senate Elmer Holt assumes office as the tenth Governor of the State of Montana upon the death of Governor Frank Henry Cooney.1933March 13Lieutenant Governor Frank Henry Cooney assumes office as the ninth Governor of the State of Montana upon the resignation of Governor John E. Erickson.1932June 18The United States of America and Canada create the Waterton-Glacier International Peace Park.1930April 1The 1930 United States census enumerates the population of the State of Montana, later determined to be 537,606, a decrease of -2.1% since the 1920 United States census. Montana remains the 39th most populous of the 48 U.S. states.

1920s