As pointed out above, natives and slaves were not citizens. This didn't mean that immigration, which was supposed to be controlled by the Federal government, would be an utter and complete failure.
In a past census, my great grandfather was included by the head of the household as a "Servant". In the census description it said "Works on the farm".
If they were able to identify Civil War veterans as part of a census, why the hell can't they ask if you're a citizen. If you're here illegally and are afraid to answer, you shouldn't be here. No government funds should be available as a result. This would certainly put an end to 'sanctuary cities' or states.

