1848 in the United States

Incumbents

Federal Government

• President: James K. Polk
• Vice President: George M. Dallas
• Chief Justice: Roger B. Taney
• Speaker of the House of Representatives: Robert Charles Winthrop
• Congress: 30th

  Governors

• Governor of Alabama: Reuben Chapman
• Governor of Arkansas: Thomas Stevenson Drew
• Governor of Connecticut: Clark Bissell
• Governor of Delaware: William Tharp
• Governor of Florida: William Dunn Moseley
• Governor of Georgia: George W. Towns
• Governor of Illinois: Augustus C. French
• Governor of Indiana: James Whitcomb , Paris C. Dunning
• Governor of Iowa: Ansel Briggs
• Governor of Kentucky: William Owsley , John J. Crittenden
• Governor of Louisiana: Isaac Johnson
• Governor of Maine: John W. Dana
• Governor of Maryland: Thomas Pratt , Philip F. Thomas
• Governor of Massachusetts: George N. Briggs
• Governor of Michigan: William L. Greenly , Epaphroditus Ransom
• Governor of Mississippi: Albert G. Brown , Joseph W. Matthews
• Governor of Missouri: John C. Edwards , Austin Augustus King
• Governor of New Hampshire: Jared W. Williams
• Governor of New Jersey: Charles C. Stratton , Daniel Haines
• Governor of New York: John Young
• Governor of North Carolina: William Alexander Graham
• Governor of Ohio: William Bebb
• Governor of Pennsylvania:
• * until July 9: Francis R. Shunk
• * July 9-July 26: vacant
• * starting July 26: William F. Johnston
• Governor of Rhode Island: Elisha Harris
• Governor of South Carolina: David Johnson , Whitemarsh B. Seabrook
• Governor of Tennessee: Neill S. Brown
• Governor of Texas: George T. Wood
• Governor of Vermont: Horace Eaton , Carlos Coolidge
• Governor of Virginia: William Smith
• Governor of Wisconsin: vacant, Nelson Dewey

  Lieutenant Governors

• Lieutenant Governor of Connecticut: Charles J. McCurdy
• Lieutenant Governor of Illinois: Joseph Wells
• Lieutenant Governor of Indiana: Paris C. Dunning , vacant
• Lieutenant Governor of Kentucky: Archibald Dixon , John LaRue Helm
• Lieutenant Governor of Louisiana: Trasimond Landry
• Lieutenant Governor of Massachusetts: John Reed, Jr.
• Lieutenant Governor of Michigan: vacant, William M. Fenton
• Lieutenant Governor of Missouri: James Young , Thomas Lawson Price
• Lieutenant Governor of New York: Hamilton Fish
• Lieutenant Governor of Rhode Island: Edward W. Lawton
• Lieutenant Governor of South Carolina: William Cain , William Henry Gist
• Lieutenant Governor of Texas: John Alexander Greer
• Lieutenant Governor of Vermont: Leonard Sargeant , Robert Pierpoint
• Lieutenant Governor of Wisconsin: John E. Holmes

  Events

January–March

• January 24 – California Gold Rush: James W. Marshall finds gold at Sutter's Mill, in Coloma, California.
• January 31 – The Washington Monument is established.
• February 2 – Mexican–American War: The Treaty of Guadalupe Hidalgo is signed, ending the war and ceding to the US virtually all of what becomes the southwestern United States.
• March 18 – The Boston Public Library is founded by an act of the Great and General Court of Massachusetts.

April–June

• April 3 – The Chicago Board of Trade is founded by 82 Chicago merchants and business leaders.
• April 23 – The Illinois and Michigan Canal is completed.
• May 19 – The Treaty of Guadalupe Hidalgo, ending the Mexican–American War, is ratified by the Mexican government.
• May 29 – Wisconsin is admitted as the 30th U.S. state.
• June 14–15 – The Liberty Party National Convention is held in Buffalo, New York. Presidential candidate Gerrit Smith establishes woman suffrage as a party plank.

  July–September

• July 19 – Seneca Falls Convention: The first women's rights convention opens in Seneca Falls, New York.
• July 26 – The University of Wisconsin–Madison is founded.
• August 14 – Oregon Territory is established.
• August 19 – California Gold Rush: The New York Herald breaks the news to the East Coast of the United States that there is a gold rush in California.
• September 12 – One of the successes of the Revolutions of 1848, the Swiss Federal Constitution, patterned on the US Constitution, enters into force, creating a federal republic and one of the first modern democratic states in Europe.
• September 13 – Vermont railroad worker Phineas Gage incredibly survives a 3-foot-plus iron rod being driven through his head.

October–December

• November 1 – The first medical school for women, The Boston Female Medical School, opens in Boston, Massachusetts.
• November 7 – U.S. presidential election, 1848: Whig Zachary Taylor of Louisiana defeats Democrat Lewis Cass of Michigan in the first US presidential election to be held in every state on the same day.
• December 26 – The Phi Delta Theta fraternity is founded at Miami University.

  No fixed date

• A cholera epidemic in New York kills 5,000.
• The University of Mississippi admits its first students.
• Geneva College is founded as Geneva Hall in Northwood, Logan County, Ohio.
• Rhodes College is founded in Clarksville, Tennessee as the Masonic University of Tennessee.
• The Shaker song "Simple Gifts" is written by Joseph Brackett in Alfred, Maine.

  Ongoing

• Mexican–American War
• California Gold Rush

  Births

• January 13 – Lilla Cabot Perry, painter
• February 20 – E. H. Harriman, railroad executive
• February 22 – Emily McGary Selinger, painter, author and educator
• March 8 – LaMarcus Adna Thompson, inventor
• March 19 – Wyatt Earp, lawman and gunfighter
• March 26 – Edward O. Wolcott, U.S. Senator from Colorado from 1889 to 1901
• May 10 – Lafayette Young, U.S. Senator from Iowa from 1910 to 1911
• June 15 – Sol Smith Russell, comedian
• July 22 – Winfield Scott Stratton, miner
• August 24 – Kate Claxton, actress
• September 4 – Lewis Howard Latimer, African American inventor
• September 29 – Caroline Yale, educator
• October 6 – Webb C. Ball, jeweler and watchmaker from Fredericktown, Ohio
• October 15 – Harmon Northrop Morse, chemist
• November 2 – Stephen Mallory II, U.S. Senator from Florida from 1897 to 1907
• November 7 – B. B. Comer, 33rd Governor of Alabama, U.S. Senator from Alabama in 1920
• November 20 – James M. Spangler, inventor
• November 27 – Henry A. Rowland, physicist

  Deaths

• February 11 – Thomas Cole, landscape painter
• February 23 – John Quincy Adams, sixth President of the United States from 1825 to 1829
• March 29 – John Jacob Astor, businessman
• April 29 – Chester Ashley, U.S. Senator from Arkansas from 1844 to 1848
• May 18 - William Leidesdorff, businessman
• June 26 - Stevenson Archer, U.S. Congressman from Maryland from 1819 to 1821
• July 20 – Francis R. Shunk, politician
• August 15 - Timothy Olmstead, composer, fifer in the American Revolutionary War
• August 30 – Simon Willard, horologist
• October 25 – Dixon Hall Lewis, U.S. Senator from Alabama from 1844 to 1848
• December 31 – Ambrose Hundley Sevier, U.S. Senator from Arkansas from 1836 to 1848