Member of the Muslim Brotherhood who spent time in the U.S. in 1949 and wrote about the coutry's immorality, inspiring groups like al Qaeda. He was convicted, in 1966, of plotting the assassination of Egyptian president Gamal Abdel Nasser and was hung to death.
He went to the U.S. to continue his studies in educational administration, and on his return to Egypt wrote about its open mixing of the sexes, its materialism and racism.
After joining the Brotherhood he became the head of its propaganda, and a leading voice in its governance.
His father was a noted political activist, and young Sayyid learned both political debate and Qur'anic tradition from him.
Osama bin Laden and other leaders of the anti-Western religious movement in the Middle East were inspired by his works.