1935 Gender Transition of Czech Athlete Zdeněk Koubek: A Landmark in Sports History

Zdeněk Koubek, a celebrated Czech track athlete, made history in 1935 by transitioning and living publicly as a man, a pioneering move that garnered significant international media attention. Born Zdena Koubková in 1913, Koubek was a formidable competitor in women's athletics, achieving world records and winning medals at the 1934 Women's World Games. His journey, including a 1936 gender-affirming surgery, represents one of the earliest recorded public gender transitions in international sports.

Before his transition, Koubek excelled in various track and field events, securing five national women's titles in 1934 across distances and jumps. He set world records in the 800m and medley relay, and earned gold in the 800m and bronze in the long jump at the 1934 Women's World Games in London. Despite his athletic success, Koubek privately grappled with his gender identity, feeling increasingly like a man.

In December 1935, Koubek announced his intention to live as a man, subsequently undergoing medical examinations that diagnosed him as intersex with predominantly female characteristics. The following year, he underwent gender-affirming surgery and officially changed his name to Zdeněk Koubek. As stated in the tweet by Eli Erlick, "He went on to compete in men’s rugby in Prague," signifying his full embrace of his male identity in sports.

Koubek's transition was met with a surprising degree of public acceptance and fascination at the time, leading to international celebrity. He traveled to New York and Paris, performing in cabarets and discussing his story, which media outlets widely covered as a "marvellous story" and proof that gender transition was possible. His decision to retire from competitive athletics in 1935 also led to the revocation of his women's records and medals.

However, Koubek's public transition also played a role in the establishment of sex testing in sports, influenced by figures like Nazi official Wilhelm Knoll, who advocated for physical examinations of female athletes. This historical context highlights how Koubek's pioneering journey inadvertently contributed to policies that would later restrict intersex and transgender athletes. After World War War II, Koubek returned to sports, joining a men's rugby team in Prague, and continued to live his life as Zdeněk until his death in 1986.