The Old Man of the Mountain was a name given to Rashid ad-Din Sinan, one of the leaders of the Syrian wing of the Hashshashin sect and an important figure in the history of the Crusades.
Latin sources from the crusader states call him Vetulus de Montanis, derived from the Arabic title Shaykh al Jabal, which means prince or elder of the mountain.
According to his autobiography, of which only fragments survive, Rashid came to Alamut, the centre of the Hashshashins, as a youth and received the typical Hashshashin training. In 1162, the sect's leader Hassan II sent him to Syria, where he proclaimed Qiyamah, which in Nizari terminology meant the time of the Qa'im and the removal of Islamic law. Based on the Nizari stronghold Masyaf, he controlled various districts in northern Syria, namely Jabal as-Summaq, Ma'arrat Masrin and Sarmin.
His chief enemy was the Sultan Saladin, who had displaced the Fatimid Caliphs of Egypt and also extended his rule over Syria. Saladin twice managed to elude assassination attempts ordered by Rashid and as he was marching against Aleppo, Saladin devastated the Nizari possessions. In 1176, Saladin laid siege to Masyaf but he lifted the siege after two notable events that transpired between him and the old man of the Mountain. One night his soldiers had found the old man of the mountain and his personal guard wandering the mountains but failed to attack him because as the soldiers reported they were held back by some mystical power. Saladin suffered terrible dreams and one night Saladin awoke to find freshly baked hotcakes, the type only the Assassins made, and a poisoned dagger next to his bed. He believed the old man of the mountain himself had laid them there. Saladin promptly lifted siege and had to accept the independence of the Hasshashin principality.
His last notable act occurred in 1192, when he ordered the assassination of the newly elected King of Jerusalem Conrad of Montferrat. Whether this happened in coordination with King Richard I of England or Saladin remains speculation.
Rashid enjoyed considerable independence from the Nizari centre in Alamut and some writings attribute him with a semi-divine status. He died between 1192 and 1194 and was succeeded by men appointed from Alamut, which regained a closer supervision over Masyaf.