The indigenous Berber tribes adopted Islam, but retained their customary laws. They also paid taxes and tribute to the new Muslim administration. The first independent Muslim state in the area of modern Morocco was the Kingdom of Nekor, an emirate in the Rif Mountains. It was founded by Salih I ibn Mansur in 710, as a client state to the Rashidun Caliphate. After the outbreak of the Berber Revolt in 739, the Berbers formed other independent states such as the Miknasa of Sijilmasa and the Barghawata.