Waterboarding in WWII:

During World War II both Japanese troops, especially the Kempeitai, and the officers of the Gestapo,[67] the German secret police, used waterboarding as a method of torture.[68] During the Japanese occupation of Singapore the Double Tenth Incident occurred. This included waterboarding, by the method of binding or holding down the victim on his back, placing a cloth over his mouth and nose, and pouring water onto the cloth. In this version, interrogation continued during the torture, with the interrogators beating the victim if he did not reply and the victim swallowing water if he opened his mouth to answer or breathe. When the victim could ingest no more water, the interrogators would beat or jump on his distended stomach.[69][70][71]

Chase J. Nielsen, one of the U.S. airmen who flew in the Doolittle raid following the attack on Pearl Harbor, was subjected to waterboarding by his Japanese captors.[72] At their trial for war crimes following the war, he testified “Well, I was put on my back on the floor with my arms and legs stretched out, one guard holding each limb. The towel was wrapped around my face and put across my face and water poured on. They poured water on this towel until I was almost unconscious from strangulation, then they would let up until I’d get my breath, then they’d start over again … I felt more or less like I was drowning, just gasping between life and death.”