Abu Muhammad ʿAbdallah 'al-ʿAdil' (Arabic: عبد الله ʿAbd Allāh; d. October 4, 1227) was an Almohad Caliph, a former governor in al-Andalus who challenged and secured the murder of his predecessor, Abd al-Wahid I.

In response, the Marrakesh palace bureaucrats, led by the vizier Abu Sa'id Uthman ibn Jami'i and the regional Masmuda tribal sheikhs, engineered the election of his elderly grand-uncle as the new caliph Abd al-Wahid I, and presented this to the remaining Almohad family members as a fait accompli.

[1] Moreover, Abd al-Wahid I, despite his age, had a distinguished record and centralising tendencies, and was less likely to give the brothers free rein in al-Andalus as the young and neglectful Yusuf II had done.

But Abdallah was soon visited in Murcia by the shadowy figure of Abu Zayd ibn Yujjan, a former high bureaucrat in Marrakesh, whose fall had been engineered some years earlier by al-Jami'i, and was now serving a sentence of exile nearby in Chinchilla (Albacete).

Before the end of the summer, Abu Zakariya, the sheikh of the Hintata tribe, and Yusuf ibn Ali, governor of Tinmal, declared for al-Adil, seized the Marrakesh palace, deposed the caliph and expelled al-Jami'i and his coterie.

The Jaén governor, Abd Allah (nicknamed "al-Bayyasi", the Baezan), took a small group of followers and set up camp in the hills of Baeza, calling for open rebellion against al-Adil.

With the coup in danger of being reversed, Abdallah al-Adil made the fateful decision to begin shipping the bulk of the Almohad forces in Spain across the straits to Morocco, intending to march on Marrakesh and imposing himself on the sheikhs.

[1] Al-Adil quickly acquired a reputation for incompetence and poor military skills, which spread across the water to Morocco, emboldening the recusants and shaking the confidence of his allies.

With al-Andalus practically denuded of Almohad troops, they ravaged the lands of Jaén, the vega de Granada and by the end of the summer, al-Bayyasi had captured the city of Córdoba.

Caliph Al-Adil, his minister Abu Zayd ibn Yajjan and leading Almohad commanders were at that moment in Seville, but they did not have the manpower to challenge the Christian army in the open.