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The country that won the gold medal in the Mixed Doubles Tennis Tournament event at the Rio 2016 Olympics was the United States.
The silver medalists in the Mixed Doubles Tennis Tournament event at the Rio 2016 Olympics were Venus Williams and Rajeev Ram.
The country winning the bronze medal in the Mixed Doubles Tennis Tournament at the Rio 2016 Olympics was the Czech Republic.
The silver medal and the gold medal in the Mixed Doubles Tennis Tournament event at the Rio 2016 Olympics went to the United States.
Suzanne Lenglen and Elizabeth Ryan won 6 back in the 1920's (Ryan won 10 women's doubles altogether; she also won 7 Mixed doubles titles @ Wimbledon.)
Only one woman won gold at the 1900 Games in tennis and that was Charlotte Cooper of Great Britain. She won the women's singles competition and also won the mixed doubles competition with Reginald Doherty.
Max Mirnyi and Victoria Azarenka Belarus (BLR)
The appropriately named player is Australian tennis legend Margaret Court.
Andy Murray and Laura Robson Great Britain (GBR)
Lisa Raymond and Mike Bryan United States (USA)
Samantha Stosur won one Grand Slam singles, two in Women's doubles, and two in mixed doubles. She is Australian Pro tennis play who is famous for her powerful serve.