The Inca civilization flourished in ancient Peru between 1400-1533 CE. They built the largest empire in pre-Columbian America, spanning twelve modern countries in South America. The Incas developed advanced agricultural techniques like terracing to farm on mountainsides. They also built an extensive road network and developed a messenger system to govern their large empire. The Spanish conquest beginning in 1532 led to the fall of the Inca Empire by 1572.