Abū Ḥafṣ ʿUmar ibn al-Wāthiq (Arabic: أبو حفص عمر بن الواثق, c. 1316 – 13 November 1386), better known by his regnal name al-Wāthiq (II) bi-'llāh (Arabic: الواثق بالله, lit. 'He who holds trust through God'), was the ninth Abbasid caliph of Cairo under the Mamluk Sultanate. He was installed by Mamluk sultan Barquq, reigning from 1383 till his death in 1386.
Biography
Rukn al-Din Umar was the son of caliph al-Wathiq I, who was briefly installed as caliph by Sultan an-Nasir Muhammad in 1340. In 1382, sultan as-Salih Hajji was usurped by his regent az-Zahir Barquq. Soon after, Barquq faced significant pushback from pro-Bahri mamluk establishment against his reign. In this political climate, the reigning caliph al-Mutwakkil I was accused of being part of one of such plots. Barquq, unwilling to disturb his elites and masses by executing the caliph, instead imprisoned him. He then installed Umar as al-Wathiq (II) billah. Public opinion stayed firmly on side of al-Mutwakkil I however, but was insufficient to sway Barquq, who just released al-Mutawakkil I from prison and let him stay at his residence. Al-Wathiq II effectively remained a non-entity and died on 13 November 1386, aged 70, of an illness. Barquq then appointed his brother Zakariyya al-Musta'sim billah as his successor.