Abu Muhammad Yahya al-Laithi ibn Yahya ibn Kathir ibn Wislasen ibn Shammal ibn Mangaya (died 848), better known as Yahya ibn Yahya, was a prominent Andalusian Muslim scholar. He was responsible for introducing the Maliki school of jurisprudence in Al-Andalus. Furthermore, he is considered the most important transmitter of Malik ibn Anas' Muwatta.
He was born in the area of Algeciras to a family of Masmuda Berber origin. His grandfather had participated in the Muslim conquest of Iberia by Tariq ibn Ziyad. Later his grandfather was given the governorship of the Algeciras and Medina-Sidonia area by the first emir of Cordoba, Abd al-Rahman. His descendants, the Banu Abi 'Isa, would subsequently rise to power in Andalusi society.
Yahya ibn Yahya traveled 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 Hanifa school, as was the rest of the 8th century Islamic world. 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, the Banu Abu 'Isa, too became powerful players in Cordoban politics.
al-Laith refers to an Arab tribe, members of which were responsible for converting his ancestors in Morocco. Wislasen is a Berber name meaning he who hears/listens.
- Ibn Khallikan (2010). Ibn Khallikan's Biographical Dictionary, Vol. IV. translated: William Macguckin De Slane. Cosimo.inc. pp. 29–33. ISBN 978-1-61640-338-6.
- John Nawas Monique Bernards (2005). Patronate And Patronage in Early And Classical Islam (Islamic History and Civilization). Brill Academic Pub. p. 204. ISBN 90-04-14480-3.