In article ,
George wrote:

It was originally proposed by Benjamin Franklin and put into law in the
US to save energy during WW1.

Wikipedia excerpt:

In 1905, the prominent English builder and outdoorsman William Willett
was inspired to invent DST during one of his pre-breakfast horseback
rides, when he observed with dismay how many Londoners slept through the
best part of a summer day.[16] An avid golfer, he also disliked cutting
short his round at dusk. His solution was to advance the clock during
the summer months, a proposal he published two years later.[17] He
lobbied unsuccessfully for the proposal until his death in 1915; see
Politics for more details. Wartime Germany, its allies, and their
occupied zones were the first European countries to use DST, starting
April 30, 1916. Britain, most other belligerents, and many European
neutrals soon followed suit, but Russia and a few other countries waited
until the next year, and the United States did not use it until 1918.
Since then the world has seen many enactments, adjustments, and repeals.