Born into an Indian-Cambodian family, Isoup Ganthy joined the police where he learned to ride. He spent several years studying in France, among others perfecting his riding capabilities, allowing him to participate in the 1956 Equestrian Olympics. Upon return to his native country, Ganthy became involved in politics, working for the ministry of foreign affairs and serving as a diplomat. After the communist Khmer Rouge seized power in 1975, Ganthy found himself belonging to the wrong political faction. In September 1976, he was arrested, suspected of assisting the KGB in their plan to overthrow the pro-Chinese Khmer. Imprisoned in the infamous Tuol Sleng prison, Ganthy was forced to confess to his treason, and he died (or was killed) in prison shortly after.