Before 1776, their legal status was a combination of British Crown and Chartar Colonies. They were British territory, under British law and the direct rule of the British Crown. When the 2nd Continental Congress, who's members had no sanction under British law, authorized the creation of new legal entities called "states" they became different legal entities and creatures of that Congress.
That was the Revolution --- not the war, but the comming together of British subjects to reject British rule as a new nation, not a collection of colonies.