In early 902, Emir Ibrahim II was forced into abdication by his subjects, through the intervention of the Abbasid caliph al-Mu'tadid. Abu'l-Abbas was named as his successor, and left Sicily for Ifriqiya, leaving his army under the command of his two sons.[17] Ibrahim, in turn, resolved to make an armed pilgrimage, and took up the mantle of the holy war, aiming to go to Mecca after first conquering Byzantine fortresses in Italy. Donning the simple dress of an ascetic, he went to Sousse, where he declared his intention and started gathering volunteers to join him.[18]