Why did the strongest maratha rule in India come an end

The empire formally existed from 1674 with the coronation of Shivaji as the Chhatrapati and ended in 1818 with the defeat of Peshwa Bajirao II at the hands of the British East India Company. The Marathas are credited to a large extent for liberating most of the Indian subcontinent from Mughal rule.

Explanation:

Apart from just fighting the battle, the Maratha troops had the responsibility to protect the non-combatants from Afghans. That was the reason why Marathas suffered heavy losses even after the battle. They could not retreat quickly as they were to protect the non-combatants who were accompanying them.