Complex sentence: The inhabitants of the province before the 16th century advent of Spanish colonisation were aboriginal peoples such as the Charrúas and the Querandíes; but their culture was lost over the next 350 years.
Split into simpler sentences: The inhabitants of the province before the 16th century advent of Spanish colonisation were aboriginal peoples such as the Charrúas and the Querandíes. Their culture was lost over the next 350 years.