The
Grand Mosque seizure occurred during November and December 1979 when extremist insurgents calling for the overthrow of the
House of Saud took over
Masjid al-Haram in
Mecca,
Saudi Arabia. The insurgents declared that the
Mahdi (the "redeemer of Islam") had arrived in the form of one of their leadersMohammed Abdullah al-Qahtaniand called on Muslims to obey him.