Jacob Qirqisani was a Karaite dogmatist and exegete who flourished in the first half of the tenth century. His origins are unknown. His patronym "Isaac" and teknonym "Joseph" reflect no more than the genealogy of the biblical patriarchs, while his surname has been taken as referring to either ancient Circesium in eastern Syria, or Karkasān, near Baghdad, though no Karaite community is known in either place. He seems to have traveled throughout the Middle East, visiting the centers of Islamic learning, in which he was well-versed.
