In 1164, Bohemond was captured by Nureddin at the
Battle of Harim. Aimery assumed the regency of the principality and immediately sent a letter to
Louis VII of France requesting military aid. The rule of the patriarch was brief. Bohemond was freed, for a ransom of 150,000
dinars, in 1165 through the intervention of Manuel and
Amalric I of Jerusalem. Upon his release Bohemond visited Manuel and agreed to re-establish a
Greek patriarch in Antioch,
Athanasius I. Aimery protested this and imposed an interdict on the city. He remained in exile at his castle of
al-Quṣayr (
Xusayr) until the death of Athanasius in 1170 in an earthquake that destroyed the
cathedral of St. Peter during the liturgy. By 1180 the Byzantine emperor was treating Aimery as the legitimate patriarch, and it is not unlikely that
William of Tyre in some negotiations at Antioch and then Constantinople on behalf of Amalric of Jerusalem had reconciled them. During his exile Aimery was on good terms with the
Jacobite patriarch of Antioch,
Michael the Syrian, whom he met at Jerusalem during Easter 1167. In order to humiliate Athanasius, Aimery arranged with Bohemond III for Michael's ceremonious entry into Antioch and there Aimery welcomed him in the cathedral of Saint Peter. Michael stayed with Aimery until Easter 1169. He also invited the Jacobite to accompany him to the
Third Lateran Council in 1179, and Michael obliged him with a treatise against
Manichaeism that the Catholics could use against the
Cathars, but declined to attend. Aimery was the first Latin prelate to allow the Jacobite patriarch to appoint a
vicar, his brother Athanasius, in Antioch. ==Antioch under interdict (c. 1180–81)==