Short answers, pulled from the story.
Louis Armstrong joined the Fletcher Henderson Orchestra in 1924. This move shifted how jazz bands played rhythm forever by emphasizing the second and fourth beats instead of a two-beat meter.
Benny Goodman's orchestra played at the Palomar Ballroom in Los Angeles on the 21st of August 1935. This single engagement transformed the landscape of popular music across America and launched an era that lasted until 1946 known as the swing era.
The swing era ended due to combined pressures including military drafts, touring expenses, and a federal government excise tax imposed in 1944. The 1944 federal government imposed a 30% excise tax on dancing nightclubs which undercut markets for dance music in smaller venues.
A new swing revival emerged during the 1990s and 2000s led by Royal Crown Revue, Big Bad Voodoo Daddy, Cherry Poppin' Daddies, Squirrel Nut Zippers, Lavay Smith, and Brian Setzer. Robbie Williams released Swing When You're Winning in 2001 selling over seven million copies worldwide.
Jimmie Rodgers, Moon Mullican, and Bob Wills combined swing and blues elements to create Western swing in country music. Willie Nelson and Asleep at the Wheel continued incorporating swing elements into country music decades later.