The Nanda Empire was a strong nation based in Magadha and containing many of the kingdoms in the Ganges basin. Its armies were huge, its leaders terrifying. It was a fear for the invading Macedonians of Alexander the Great, a fear leading to a mutiny which ultimately lead to the return of the Macedonian army from the banks of the modern river Beas. Its strength was challenged by the Kingdom of Chandragupta Maurya located in north western India. Under Chandragupta Maurya, it supplanted the long-established and powerful Nanda Empire. Nanda Army strength in the east was 200,000 infantry, 80,000 cavalry, 8,000 chariots, and 6,000 war elephants. The forces of Chandragupta remain unknown along with the exact details of the conflict.