The Zengid dynasty was a Muslim dynasty of Oghuz Turkish origin, which ruled parts of the Levant and Upper Mesopotamia on behalf of the Seljuk Empire. The dynasty was founded by Imad ad-Din Zengi.
In 1146 Imad al-Din Zengi was besieging the fortress of Qal Ja'bari when he was assassinated on September 15 by one of his servants who wanted to escape punishment. His forces were scattered, but Imad ad-Din Zengi's two sons were able to regain control and to divide informally the empire. Saif ad-Din succeeded him in Mosul and the Jezirah (northern Iraq) and ruled here till 1149.
In 1148, together with his brother, Saif ad-Din marched south to help defend Damascus during the Second Crusade. The atabeg of the city, Mu'in ad-Din Unur, however, refused them entrance, using the presence of Zangi's sons to convince the Franks to release the siege.
The above shown silver Dirham of Saif ad-Din of Mosul mint depicting a classical portrait facing left. The reverse of a coin illustrates the Arabic inscription.
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