The Zoot Suit, characterized by an oversized jacket with large lapels, padded shoulders and baggy pants which were cuffed at the ankles (with a wide brimmed fedora hat generally accompanying) was first popularized by young teenage “hepcats.”

ZOOT SUIT (n.): the ultimate in clothes. The only totally and truly American civilian suit.
— Cab Calloway, The Hepster’s Dictionary, 1944

It popped up in the early 1940’s among the “jitterbug” dancers and was popularized when entertainers such as Frank Sinatra began wearing them.

The suit was first worn in Harlem, New York but the fad ended quickly when the War Production Board restricted the amount of material that could be used in men’s clothing.