The next beylerbey was Hayreddin's son Hasan, who assumed the position in 1544. He was a Kouloughli or of mixed origins, as his mother was an Algerian Mooresse. Until 1587 Beylerbeylik of Algiers was governed by Beylerbeys who served terms with no fixed limits. Subsequently, with the institution of a regular administration, governors with the title of pasha ruled for three-year terms. The pasha was assisted by an autonomous janissary unit, known in Algeria as the Ojaq who were led by an agha. Discontent among the ojaq rose in the mid-1600s because they were not paid regularly, and they repeatedly revolted against the pasha. As a result, the agha charged the pasha with corruption and incompetence and seized power in 1659.