How did the Rashtrakutas become powerful?

Rashtrakutas became powerful in the following manner:

1. Rashtrakutas were subordinates to the Chalukyas of Karnataka.
2. In the mid-eighth century Dantidurga, a Rashtrakuta chief, overthrew his Chalukyan overlord.
3. He performed a ritual called Hiranya-garbha with the help of Brahmanas.
4. This ritual was, then, considered to lead the rebirth of the sacrificer as Kshatriya, even if he was not Kshatriya by birth.