Sarmatism (or Sarmatianism) is a term designating the formation of the dominant Baroque culture and ideology of the szlachta (nobility) of the Polish-Lithuanian Commonwealth from the 16th to the 18th centuries. Together with "Golden Liberty," it formed a central aspect of the Commonwealth's culture. At its core was the unifying belief that the people of the Polish Commonwealth descended from the ancient Sarmatians, the legendary invaders of Slavic lands in antiquity.