When the US declared itself independent in 1776, did it simply consider all people (of a certain demographic) already living in the US citizens? Or did these people have to apply to become citizens somehow? For example, did Benjamin Franklin become a US citizen as soon as the US began existing?
The better to secure and perpetuate mutual friendship and intercourse among the people of the different states in this union, the free inhabitants of each of these states, paupers, vagabonds and fugitives from justice excepted, shall be entitled to all privileges and immunities of free citizens in the several states*
Theoretically, this just passed US citizenship question to the states. In practice, free Negroes were never granted citizenship rights in southern states, and the 1857 Supreme Court Dred Scott decision denied US citizenship for all Negroes regardless of the state they inhabited.