He was a Saqaliba, usually Slavic children that were captured, castrated, sold as slaves in Spain, and educated in the Islamic culture and religion.
It is possible that Labib left Cordoba after Hisham II was deposed in AH 400 (1009/1010).
This arrangement only lasted until AH 411 (1020/1021), when Labib was forced to leave Valencia and return to Tortosa.
Soon after this Mujahid was replaced by Abd al-Aziz ibn Ámir as the ruler of The Taifa of Valencia.
[4] In AH 427 (1035/1036), Labib declared allegiance to Hisham II (who was most likely dead after the Berbers sacking Cordoba in 1013) as a symbol of his legitimacy, after the ruler of the Taifa of Seville, Abu al-Qasim Muhammad ibn Abbad claimed he had reappeared.