Why did the founding fathers include the bill of rights with the consititution

Federalists argued that the Constitution did not need a bill of rights, because the people and the states kept any powers not given to the federal government. Anti-Federalists held that a bill of rights was necessary to safeguard individual liberty.

Explanation:

the  wilmot proviso  was designed to eliminate  slavery  within the  landacquired as a result of the mexican war (1846-48). fearing the addition of a pro-slave territory, pennsylvania congressman david  wilmot proposedhis amendment to the bill.