Complex sentence: The region was inhabited by Romanians and Nogai Tatars through the Middle Ages, but became a home to several other ethnicities and religious groups during 19th century Bessarabian Bulgarians, Bessarabian Germans, Gagauzians, Lipovan Russians, who settled in compact areas.
Split into simpler sentences: The region was inhabited by Romanians and Nogai Tatars through the Middle Ages, but became a home to several other ethnicities and religious groups during 19th century. The examples are Bessarabian Bulgarians, Bessarabian Germans, Gagauzians and Lipovan Russians who settled in compact areas.