TO ENFRANCHISE. To make free to incorporate a man in a society or body politic. Cunn. L. D. h. t. Vide Disfranchise.

Source: Bouvier's Law Dictionary (1856).
enfranchise.
early 15c., "to set free," from O.Fr. enfranchiss-, prp. stem of enfranchir "to set or make free; grant a franchise to;" from en- "make, put in" (see en- (1)) + franc "free" (see franchise). Meaning "to admit to membership in a state" (generally with reference to voting privileges) is from 1680s. Related: Enfranchised; enfranchisement.

Source: Online Etymology Dictionary
One's person incorporates them into another domain.
The joining of one domain to another.

The birth certificate and name is for purposes of joining he or she that claims such document on assumpsit to the domain of judicial or revenue schemes.