Ottoman soldiers would take European Christian males, aged 8 to 20, from Eastern, Southern and Southeastern Europe, and relocate them to Istanbul, where they would be trained. The fact that many were taken forcibly from their parents has been the subject of criticism. The devshirme was often resented by locals though some Christian families volunteered their sons, as service offered good career options, specifically Albanians and Bosnians according to William Gervase Clarence-Smith. Recruits sometimes used their positions to help their family. The boys were forced to convert to Islam. Muslims were not allowed into the system (with some exceptions), but some Muslim families smuggled their sons in anyway.