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Daylight Saving Time Once Known As 'War Time'

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It's that time of year when we spring forward and are happy to get home from a busy day while it's still light out.

Did you know?

The tradition of "springing" forward one hour was once nicknamed "war time."
The idea of daylight saving time originated in New Zealand in the 1800s, although it wasn’t implemented there until 1927.

In America, daylight saving time first became official on March 19, 1918, when the Standard Time Act was signed into law. It allowed for additional daylight hours to be added into the day to help save energy costs during World War I. The law also established the five time zones that we now know.

Poster showing a man writing a postcard with the U.S. Capitol in the background.
Lobby Poster
A poster from 1918 encourages citizens to write a postcard and lobby Congress in support of daylight saving time.
Photo By: Library of Congress photo
VIRIN: 180218-O-ZZ999-111C

The part of that law pertaining to daylight saving time was only in effect for about a year and a half, though, before it was repealed due to the war’s end, despite President Woodrow Wilson vetoing the repeal.

It wasn’t until World War II began that the issue came up again. In February 1942, Congress implemented a law instating a national daylight saving time to help conserve fuel and "promote national security and defense," which is why it was nicknamed "war time." The time zones were even known as that: Eastern War Time, Pacific War Time, etc.

A CV-22 Osprey sits on a field at sunrise with a clock superimposed behind it.
Spring Forward
DOD service members, civilians and contractors: don't forget to spring your clocks forward one hour this weekend for daylight saving time!
Photo By: Air Force Senior Airman Andrea Posey
VIRIN: 170311-F-MT297-0824C

But when the war ended in 1945, the law was once again repealed so individual states could establish their own standard time.

For the next two decades, there were no set rules for daylight saving time, which caused a lot of confusion for the transportation and broadcast industries. That changed for good in 1966, when Congress passed the Uniform Time Act that set a national standard time that permanently superseded local times. It established daylight saving time from the last Sunday in April to the last Sunday in October.

Portions of the law have been changed a few times since, including to the dates when the "spring" forward and "fall" back happen. The current policy was implemented by President George W. Bush in 2005, extending daylight saving time by a few weeks. It now starts on the second Sunday in March and ends on the first Sunday in November.

A close-up of an ornate silver and gold clock.
Major General Clock
The Major General Edwards Clock was rededicated Dec. 1, 2018, and now stands outside the office of the Massachusetts National Guard's adjutant general at Joint Force Headquarters Massachusetts, Hanscom Air Force Base, Mass.
Photo By: Army Sgt. Alfred Tripolone III
VIRIN: 181129-Z-JM688-182C

While daylight saving time is a federal mandate, states can opt out of it by passing a state law. Hawaii and Arizona don’t observe it, though the Navajo Nation in northeastern Arizona does. Most American territories, including Puerto Rico and Guam, don’t observe it, either.

So if you’ve ever wondered where that tradition comes from, now you know!

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