Watson outlasted Chang 7-5, 5-7, 7-6 (4) in 3 hours, 11 minutes to end the long drought for her country -- just three weeks after Laura Robson became the first British woman in 22 years to even reach a WTA final.
Both Watson and Chang were appearing in their first career final and showed signs of nerves. Watson wasted a match point at 5-3 in the second set, then saved four when Chang led 5-4 in the third. The match featured 14 breaks of serve, including seven in the first set.
Watson's victory marked another milestone for British tennis, after Andy Murray finally broke a 76-year Grand Slam drought on the men's side by winning the U.S. Open this year.
The last British woman to win a WTA title was Sara Gomer in 1988.