Regarded as a pioneer of Dutch competitive swimming, Marie Baron had an incredible run of success during the 1920s. From 1923 to 1929 Baron won 13 national swimming titles, with her best performance undoubtably coming in 1927, when she won six titles. She also set more than a dozen Dutch swimming records, as well as world records in both the 200 and 400 metres breaststroke.
Baron was selected to swim in the 200 metres breaststroke at the 1924 Paris Olympics. She swam in the first heat of the race but was disqualified when it was deemed she had made an illegal turn after touching the wall with only one hand instead of two. Baron’s time of 3:22.6 was five seconds faster than anyone else but her disqualification ruled her out of the final and almost certainly the gold medal. At the Paris Games she also swam in the 4 × 100 metres freestyle relay, with the Dutch team finishing sixth. Four years later Baron won silver in the 200 metres breaststroke at the 1928 Amsterdam Games, finishing just behind the German swimmer Hilde Schrader. She also competed in the platform diving event in Amsterdam where she just missed out on another medal with fourth. Baron retired from swimming late in 1929 after announcing her engagement to her future husband. Sadly she died in July 1948 at the age of 40 after suffering with a long illness.