When did Serena Williams win her first major singles title?

By the late 1990s, tennis fans were starting to whisper about this teenager who hit the ball harder than most men and wore colorful outfits that made the traditional tennis establishment clutch their pearls. The tennis world might not have been ready for Serena Williams, but she was ready for it. After having already won three major doubles titles (two in mixed and one with her sister Venus), she won her first singles title at the 1999 US Open, defeating world number one Martina Hingis. The victory made her the youngest American to win a Grand Slam singles title since Tracy Austin in 1979, and tennis commentators started running out of superlatives to describe what they were witnessing. But one title at the 1999 US Open wasn't enough for Williams, and she teamed up with Venus again to grab the doubles championship too. It was the beginning of what became the most dominant career in modern tennis, though nobody at the time could have predicted she'd eventually rack up 23 Grand Slam singles titles and spend most of the next two decades terrorizing opponents with a legendary serve.