When was the last time a nuclear weapon was used in warfare and who by/against?
In warfare, the nuclear bomb has only been used twice in history. Thousands of other nuclear bombs have been tested, but only twice have they been purposefully used to attack another country. Both nuclear weapons were used by the Americans against the Japanese in WWII. Hiroshima, Japan – Monday, August 6th,1945 Nagasaki, Japan – Thursday, August 9th,1945 Therefore, to answer your question the last time a nuclear weapon was used in warfare was on August 9th, 1945 by the Americans against Japan in WWII.