Humayd hailed from an Arab noble family (ashraf) settled in the Ghuta plain around Damascus.
Beginning with his great-grandfather, Ma'yuf ibn Yahya al-Hujari, his family had loyally served the Abbasids and risen to a prominent position in Syria.
[1] In 806, according to al-Tabari, Caliph Harun al-Rashid placed him in charge of "the Levant coastlands of the eastern Mediterranean as far as Egypt".
[4][5] It is sometimes considered that before attacking Rhodes, Humayd led his fleet to the Peloponnese, where he either assisted or even fomented a revolt by the local Slavs, leading to the unsuccessful siege of the port city of Patras.
[6] In the late 810s or the 820s, following a brief tenure by his father, Humayd governed Damascus as deputy to an absent governor of the Jund Dimashq; Paul M. Cobb theorizes that the latter was Nasr ibn Khamza, meaning that Humayd's tenure may have lasted until the appointment of Abu Ishaq, the future al-Mu'tasim, as governor of Syria in 828.