Explain the wording of the immigration policy of this nation at its founding you filthy fucking liar.

Germans and Catholics were only debatably White.

Is that the definition you are using?

Only in so far as nation and country (and religion too for a while) were synonymous throughout the overwhelming majority of human history.

Absolutely not. Remember, most people lived under monarchies. Nations existed both without states, and between states. Feudalism didn't take nations of people into account. Hell, the Hapsburgs personally owned multiple states, and their subjects were many peoples and many religions. A state was claimed by inheritance from family, not whether or not a nation of people existed from it.