George Washington was the first president to use the veto. What was the bill and why did Washington veto it?
Apportionment is a term used to describe how Congress divides the seats in the House of Representatives among the states based on U.S. census figures.
Washington thought Jefferson's original formula gave the northern states an unfair advantage. The veto was sustained by Congress and a rewritten version of the bill was later signed by Washington.
Washington only used the veto one more time during his term in office.
Read all about apportionment at the U.S. Census Bureau site.