Yahya was born in the area of
Algeciras to the Banu Abi Isa family. His grandfather, Abu Isa Kathir, the eponymous of the family, was a
Masmuda Berber soldier and a
mawla of the Banu Layth of
Kinana, thus the nisba
al-Laythi.
Abd al-Rahman I rewarded Kathir by giving him the governorship of Algeciras, then Sidonia and later again Algeciras, where he died and was buried. Yahya ibn Yahya travelled to the East at a young age and studied with
Malik ibn Anas, becoming an ardent follower of his. Al-Andalus in his time was dominated by the followers of imam
al-Awza'i – due to the fact that most Arabic Muslim conquerors came from
Syria – beside different other schools of Jurisprudence according to imam
al-Dhahabi in his tarikh al-Islam al-Kabir when mentioning Yayha's teacher Shabtun (Zaid ibn Abdarrahman al-Lakhmi). Returning to Al-Andalus, he focused on his scholarly work. As a member of the
shura (the advisory board that the emir and judges had to consult), he had an enormous influence on the nomination of legal positions. Still, he himself never accepted a legal position. In his role as member of the
shura he became close to the ruler of Al-Andalus, who was apparently impressed with his intelligence and authority on Islamic matters. He thus grew to become the most influential member of the
shura, giving him the opportunity to nominate judges who also favored the Maliki school. At the end of his life, the Maliki school was the most important in Al-Andalus. At one point he was accused of taking part in a rising, after which he fled
Cordoba to live amongst the Masmuda tribes near
Toledo. He was pardoned by emir
Al-Hakam I and allowed to return. His descendants became one of the greatest families of the 9th and 10th centuries, due in part to the fame of their ancestor. But among them personalities with their own light also appear, who maintain the power and influence of the family due to their individual merits. == His place in Andalusia ==