The Inca people lived on the continent of South America before the Spanish conquest. They inhabited a vast area that included present-day Ecuador, Peru, Bolivia, Chile, and Argentina. The Inca civilization peaked in the 15th and early 16th centuries, just before the arrival of the conquistadors led by Francisco Pizarro. The Inca were known for their advanced agricultural techniques, engineering feats, and complex social hierarchy, which revolved around the divine rule of the Sapa Inca (emperor). Today, their legacy is still present in many Andean countries, manifested in their intricate stonework, textiles, and music, and the Quechua language, which is still widely spoken.