The rebellion abated, but direct papal pressure induced Frederick to mass transfer all his Muslim subjects deep into the Italian hinterland.[11][12][13][14] In 1224, Frederick II expelled all Muslims from the island transferring many to Lucera (Lugêrah, as it was known in Arabic) over the next two decades. In this controlled environment they could not challenge royal authority and they benefited the crown in taxes and military service. Their numbers eventually reached between 15,000 and 20,000, leading Lucera to be called Lucaera Saracenorum because it represented the last stronghold of Islamic presence in Italy.