Deut. 20:10 When thou comest nigh unto a city to fight against it, then proclaim peace unto it.
20:11 And it shall be, if it make thee answer of peace, and open unto thee, then it shall be, [that] all the people [that is] found therein shall be tributaries unto thee, and they shall serve thee.
20:12 And if it will make no peace with thee, but will make war against thee, then thou shalt besiege it King of kings' Bible - Deuteronomy