"5 March 1512 – 2 December 1594"
Everything was a bit complicated in that region in the medieval period. In the C16, you immediately come up short with the concept of "Germany".
Germany the state - indeed, but German as a culture/language/nationality(in the contemporary definition) was definitely there.
Same with Italy, which wasn't a single state until the mid XIX century. Over to the east states lost independence and remained so for hundreds of years, only to re-emerge in the XX century.
My point is that state as an entity doesn't fully define one's identity.
He was born in the County of Flanders, current day East Flanders and moved to Germany at the age of 40.
https://en.wikipedia.org/wiki/Gerardus_Mercator