Antonius Johannes Geesink was a Dutch 10th dan judoka. He was the first non-Japanese judoka to win gold at the World Judo Championships, a feat he accomplished in 1961 and 1965. He was also an Olympic Champion, having won gold at the 1964 Summer Olympics in Japan, and won a record 21 European Judo Championships during his career.

Judo is an unarmed modern Japanese martial art, combat sport, Olympic sport, and the most prominent form of jacket wrestling competed internationally. Judo was created in 1882 by Kanō Jigorō as an eclectic martial art, distinguishing itself from its predecessors due to an emphasis on "randori" instead of "kata" alongside its removal of striking and weapon training elements. Judo rose to prominence for its dominance over established jujutsu schools in tournaments hosted by the Tokyo Metropolitan Police Department, resulting in its adoption as the department's primary martial art. A judo practitioner is called a "judoka" , and the judo uniform is called "judogi" .