Ali ibn Yusuf (also known as "Ali Ben Youssef") was the 5th Almoravid emir reigning from 1106 to 1143.
Ali ruled from Morocco and appointed his brother Tamim ibn Yusuf as governor of Al-Andalus. Ali expanded his territories in the Iberian Peninsula by capturing Zaragoza in 1110 but eventually lost it again to Alfonso I, King of Aragon, in 1118. Cordoba rebelled against the Almoravids in 1121.
The Battle of Ourique was fought on 25 July 1139 between the forces the Almoravid led by Ali Ibn Yusuf and Portuguese Prince Afonso Henriques (of the House of Burgundy). Despite the fact that the Christian Portuguese forces were strongly outnumbered, the Muslim armies were weakened by internal leadership problems, which led to Afonso Henriques's victory and subsequently his proclamation as King of the Portuguese, as Afonso I.
The above shown gold Dinar was issued under his reign from Isbiliya (Seville) mint. Both side of a coin inscribed with beautiful Arabic calligraphy.
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