Sofa refers to an infantryman in the Samorian army or a slave soldier of the Mali empire. Sofa translates into English as 'guardian of the horse' or 'father of the horse.'
"Sofas were recruited from 'jonow' (slaves) captured in battle or bought from afar. They could be depended on in most instances for obedience, since their livelihood depended entirely on their master. The institution of slavery in the Mali Empire heavily rewarded loyalty, and jonow could rise to civil or military positions of prominence. Jonow became part of their master's clan, and were often freed after a certain amount of years. As part of the clan, jonow were expected to accompany their masters into battle and handle his horse and weapons."