Conversation so far:
Who was Ludwig Mies van der Rohe?
Ludwig Mies van der Rohe, born Maria Ludwig Michael Mies; March 27, 1886 – August 17, 1969) was a German-American architect.
When was Ludwig Mies van der Rohe born?
Maria Ludwig Michael Mies was born March 27, 1886.

Question: Where was he born?
Self-contained rewrite: Where was Ludwig Mies van der Rohe born?