The term PERUVIAN OF OLD can be broken down into two crossword solutions: INCA (4 letters) and INCAN (5 letters). The INCA Empire was a South American civilization that flourished in the Andes Mountains from the 12th to 16th centuries. It was the largest empire in pre-Columbian America and was highly advanced in terms of architecture, engineering, and agriculture. The Incas were known for their impressive stone structures, such as Machu Picchu, and their intricate road systems. The Incas were also renowned for their sophisticated system of government, which included a complex bureaucracy and a hierarchical social structure. The Incas were polytheistic and believed in an afterlife. They were also known for their art, music, and literature. The Incas were eventually conquered by the Spanish in the 16th century, but their legacy lives on in Peru today.