The Mansabdari system, introduced in medieval India, was primarily aimed at ensuring clean administration. It was implemented by the Mughal Emperor Akbar in the late 16th century and continued to be used by his successors. The system was a hierarchical ranking system that encompassed both military and civil administration.

Below is a detailed explanation of the reasons behind the introduction of the Mansabdari system:

1. Centralized Administration:
- The Mughal Empire was vast and diverse, spanning across different regions and cultures. To effectively govern such a large empire, a centralized administration was required.
- The Mansabdari system helped in establishing a well-organized administrative structure, with clearly defined ranks and responsibilities.

2. Recruitment and Organization of the Army:
- The Mansabdari system played a crucial role in organizing and managing the Mughal army.
- It facilitated the recruitment of soldiers and officers, ensuring that they were suitably qualified and loyal to the emperor.
- Each Mansabdar (officer) was assigned a specific number of soldiers according to their rank or 'mansab'. This helped in maintaining a disciplined and efficient military force.

3. Revenue Collection and Land Revenue Administration:
- The Mansabdari system also provided a framework for revenue collection and land revenue administration.
- Mansabdars were responsible for collecting taxes from the assigned territories, which contributed to the imperial treasury.
- The revenue collection process was streamlined, reducing corruption and ensuring a fair and efficient system.

4. Control and Surveillance:
- The system allowed the emperor to exercise direct control and surveillance over the nobles and officials.
- Mansabdars were required to report to the emperor regularly, providing updates on their activities and revenue collection.
- This helped in maintaining transparency and accountability in the administration.

5. Religious Harmony and Social Cohesion:
- The Mansabdari system promoted religious harmony by incorporating people from diverse backgrounds into the administration.
- It allowed individuals of different religions, castes, and ethnicities to hold high ranks in the empire, fostering a sense of inclusivity and social cohesion.

Overall, the Mansabdari system was introduced to establish a well-structured and efficient administrative system in medieval India. It aimed to ensure clean governance, efficient military organization, revenue administration, and social harmony. The system played a significant role in the stability and success of the Mughal Empire.