Complex sentence: In the 1670s, the Schwarzenbergs established their primary seat in Bohemia and, until 1918, their main residence was in Český Krumlov, Bohemia (now in the Czech Republic).
Split into simpler sentences: In the 1670s, the Schwarzenbergs established their primary seat in Bohemia. Until 1918, their main residence was in Český Krumlov, Bohemia (now in the Czech Republic).