Ethelda Marguerite Bleibtrey (27 February 1902 – 6 May 1978 in West Palm Beach, Florida), also known by her married name Ethelda Schlatke, was an American competition swimmer, three-time Olympic gold medalist, and former world record-holder in multiple events. She started swimming to help recover from polio, which she contracted in 1917.
In 1919, she was arrested for nude swimming when she removed her stockings at a pool where it was forbidden to bare the lower female extremities for public bathing. The subsequent public support for Bleibtrey led to the abandonment of stockings as a conventional element in women's swimwear.
- Bleibtrey was a dominant backstroke swimmer, but entered and won gold medals in three freestyle events when there were no women's backstroke events at the 1920 Antwerp Olympics in Belgium.
- She won a gold medal as member of the winning U.S. team in the women's 4×100-meter freestyle relay, together with teammates Margaret Woodbridge, Frances Schroth and Irene Guest. The American relay team set a new world record of 5:11.6 in the event final.
- Individually, Bleibtrey received gold medals and set world records in the women's 100-meter freestyle (1:13.6) and the women's 300-meter freestyle (4:34.0).
- She was inducted into the International Swimming Hall of Fame as an Honor Swimmer in 1967.