January 6 - The first telephone message sent by a submerged submarine is transmitted.
January 25 - The battleship Maine arrives in the Havana, Cuba harbor to protect the interests of Americans who are being brutalized by the Spanish government.
February 1 - The first automobile insurance policy is issued by Travelers Insurance Company of Hartford, Connecticut.
February 8 - The first envelope folding and gumming machine is patented by John Ames Sherman of Worcester, Massachusetts.
February 15 - The battleship Maine mysteriously explodes while in the Havana, Cuba harbor. Although no clear evidence of foul play could be produced, this event would lead to the Spanish-American War.
March 9 - Congress appropriates $50 million for national defense.
March 16 - The first practical submarine made by John P. Holland is submerged off Staten Island, New York and remains underwater for a little longer than an hour.
March 31 - The first sale of an automobile is transacted.
April 10 - President McKinley delivers a War Message and gives Congress his opinion of the Spanish response to peace initiatives.
April 19 - Congress adopts a War Resolution for Cuban independence from Spain.
April 22 - Congress passes the Volunteer Army Act which calls for the organization of a first Volunteer Cavalry, which later became known as the Rough Riders.
April 24 - Spain declares war on the U.S.
April 25 - The U.S. declares that a state of war with Spain has existed since April 21st.
May 1 - The U.S. launches a surprise naval attack on the Philippines.
May 12 - The U.S. bombards San Juan, Puerto Rico.
May 25 - The first American troops leave for Manila.
June 10 - The U.S. Marines land at Guantanamo Bay, beginning the invasion of Cuba.
June 13 - The Yukon Territory is organized.
June 24 - The Rough Riders win the first land battle at Las Guasimas, Cuba.
July 1 - San Juan Hill in Cuba is occupied by American troops.
July 3 - American troops take the deserted Wake Island on their way to the Philippines.
July 8 - Admiral Dewey takes Isla Grande near Manila.
July 26 - Spain requests peace terms with the U.S.
September 13 - H. W. Goodwin of Newark, New Jersey patents celluloid photographic film.
November 9 - Washington is admitted to the Union as the 42nd state.
December 10 - The U.S. and Spain signs a peace treaty and the U.S. is given Cuba, Puerto Rico and other West Indian Islands, Guam and the Philippines.
