Abu Zubaydah (Arabic: ابو زبيدة; born 12 March 1971 as Zayn al-Abidin Muhammad Husayn) is currently in U.S. custody in Guantanamo Bay, Cuba, as a detainee in the war on Terror. Zubaydah's name is often transliterated as Abu Zubaidah, Abu Zubeida, or Abu Zoubeida. Born Zein al-Abideen Mohamed Hussein (Arabic: زين العابدين محمد حسين), he is also known by over thirty-five aliases.
Born in Saudi Arabia, Abu Zubaydah moved to the West Bank as a teenager where he joined in Palestinian demonstrations against the Israelis.
Abu Zubaydah moved to Afghanistan in 1991 to assist the mujahideen in their fight against the Afghan and Soviet Communists. In 1992, while fighting for the mujahideen Abu Zubaydah was injured from a mortar shell blast which left shrapnel in his head and caused severe memory loss, as well as the loss of his ability to speak for over one year. Abu Zubaydah eventually became involved in the jihad training camp known as the Khalden Camp.