Q. Who defeated Pallava King Mahendravarman I?
Answer:
Pulakesin II
Notes: Pallava King Mahendravarman I was defeated by the Chalukya King Pulakesin II. Narasimhavarman I, Mahendravarman's son, avenged this defeat by killing Pulakesin II in the Battle of Vatapi in 642 AD and capturing the capital Vatapi. He earned the title 'Vatapikonda' after this victory.