There was an unknown number of Muslim slaves living in the Kingdom. There was a very large slave market in Acre that functioned throughout the twelfth and thirteenth centuries. Italian merchants were sometimes accused of selling Southeastern European Christians as slaves along with Muslim slaves. Slavery was less common than ransom, especially for prisoners of war; the large numbers of prisoners taken during raids and battles every year ensured that ransom money flowed freely between the Christian and Muslim states. Escape for prisoners and slaves was probably not difficult, as the inhabitants of the countryside were majority Muslim, and fugitive slaves were always a problem. The only legal means of manumission was conversion to (Catholic) Christianity. No Christian, whether Western or Eastern, was permitted by law to be sold into slavery.