What methods did the Incas use to unity their large empire?

The Incas were able to unite their large empire through a combination of political, military, economic, social, and cultural methods. Some of these methods include:

1. Military conquest: The Incas used force to expand their territory and subdue neighboring groups. They had a well-trained, disciplined, and organized army that allowed them to conquer other regions easily. Once conquered, local populations were often required to provide soldiers for the Inca army.

2. Diplomacy and alliances: The Incas were skilled diplomats, and often formed alliances with neighboring groups through marriage or other means. They established relations with weaker groups and provided them with protection, food, and other resources in exchange for allegiance.

3. Tactic of "divide and rule": The Incas often played rival groups against each other to weaken their enemies and maintain control over a conquered region. They prevented rebellions by keeping local leaders in check and promoting internal competition and rivalries among them.

4. Redistribution of land and resources: The Incas often redistributed land and resources to maintain control over conquered populations. They would take possession of valuable land and resources and then redistribute them among loyal supporters, including local elites, in order to secure their allegiance.

5. Infrastructure and communication: The Incas built an extensive road network that connected all parts of the empire, facilitating transportation, communication, and administrative control. They also used runners (chasquis) to deliver messages and carry goods throughout the empire, ensuring a constant flow of information and goods between the capital and the most distant provinces.

6. Language and education: The Incas promoted the use of the Quechua language as a unifying factor throughout the empire. They also established an education system where they trained the sons of local rulers in Inca customs, language, religion, and governance. This approach helped to create a new generation of local elites who were more loyal to the Inca Empire.

7. Religion and ideology: The Incas were able to foster unity in their empire through a shared religious and ideological framework. They believed that the Inca leader, the Sapa Inca, was the divine son of the sun god Inti, which reinforced his authority and the legitimacy of Inca rule. They also built numerous religious sites throughout the empire, which served not only as places of worship but as symbols of the power and reach of the Inca state.

8. Forced resettlement: The Incas practiced a policy of forced resettlement, known as "mitmaq," wherein conquered populations were relocated to other parts of the empire, and loyal Inca citizens were moved into the newly conquered territories. This strategy broke up existing power structures and facilitated the assimilation of new groups into the Inca societal and political system.

Overall, the Incas used a multifaceted approach to unite their vast empire by successfully integrating diverse cultures and populations through methods involving military force, diplomacy, infrastructure development, culture, and religion.