What convinced the southerners to agree to help pay the national debt in the late 1790s?

The action that led the Southerners to compromise on the national debt was that they had to pay a lot of money to the northern states to make a deal they wanted to move the capital to the southern part of the United States which is now WashingtonD.C.

(The 1st president George Washington's capitol was in New York instead of D.C.)