
Senate Sergeant at Arms Charles Higgins turns forward the Ohio Clock for the first Daylight Saving Time, while Senators William Calder (NY), William Saulsbury, Jr. (DE), and Joseph T. Robinson (AR) look on, 1918. Photo Credit: Senate Historical Office
As railroads dominated the landscape of the American West and Canada, standard time in time zones became a necessity. By 1883 standard time was initiated but was not signed into U.S. law until March 19, 1918 with the Standard Time Act.

World War I poster showing Uncle Sam turning a clock to Daylight Savings time as a clock-headed figure throws his hat in the air. The clock face of the figure reads “One hour of extra daylight.” The poster was sponsored by United Cigar Stores Company. Photo Credit: Library of Congress
The Standard Time Act also established daylight saving time (DST). Signed into law during World War I, “War Time” was meant to conserve fuel needed to produce electric power. The United States was hardly the mastermind of this wartime initiative. The Central Powers, notably Germany and Austria, were the forerunners of wartime DST when they started the program on April 30, 1916 by advancing the time by one hour until October. Three weeks later, many European countries and some Canadian territories followed suit.
It took the United States two years to formally adopt this program on March 19, 1918. The program established standard time zones and set summer DST to begin at the end of the month. “War Time” ran for seven months but once the war ended, the Standard Time Act was dropped and DST became a local option, however standard time in time zones still remained in law. Some states (Massachusetts and Rhode Island) and cities (New York, Philadelphia and Chicago) continued with DST.

President Franklin D. Roosevelt signs a declaration of war in 1941. “War Time,” a variation on daylight-saving time, followed. Again the idea was to save fuel. Photo Credit: Hulton Archive/Getty Images/NPR
During World War II, President Roosevelt re-established “War Time,” for the same reasons as the First World War – to conserve energy. Since DST was a hot-button issue, the Act explicitly states that it will end. ”This Act cease to be in effect six months after the termination of the present war or at such earlier date as the Congress shall be concurrent resolution designate.” The program ran from February 9, 1942 to September 30, 1945.
After World War II, DST varied again among states and cities, which naturally caused confusion for broadcasting and service companies. In 1966, Congress passed the Uniform Time Act of 1966 which established a beginning and end date for DST for those local jurisdictions that decide to use it.
The “energy crisis” in the 1970’s spurred Congress and President Nixon to enact the Emergency Daylight Saving Time Energy Conservation Act that enacted earlier starting dates for DST. The Act was in response to the Arab oil embargo and the Department of Transportation estimated that 100,000 barrels of oil was saved each day because of the Act.
Currently most areas in the United States observe DST, except for Arizona (the Navajo Nation does observe DST), Hawaii and overseas territories.
Sources
“Daylight Time”, United States Naval Observatory.
“A Time-Change Timeline”, NPR. March 9, 2007.
The Act of 1918 & the Act of 1942.
History of Daylight Saving Time