Ajatasatru, the Haryanka Emperor from 512-461 BCE, governed a large kingdom that included northern India from Bengal to the Punjab, and into Nepal.
Chandragupta Maurya, the Mauryan Emperor from 340-298 BCE, united India, defeated Alexander the Great, and created the largest empire of its time by taking over Persian territories.
Ashoka was a Mauryan Emperor who ruled from 304-232 BCE and presided over an empire that stretched across most of the Indian subcontinent.
Samudragupta, the Gupta Emperor who ruled from 315-380 CE, made neighbouring states in Iran and Afghanistan his tributaries, and they continued to pay taxes until around 500 CE.
Pulakesi II was a Chalukya King from 610-642 CE who expanded his rule over southern territories by securing victories in western India and eastern Deccan.
Raja Raja Chola I was a Chola King from 947-1014 CE who conquered southern India, most of Sri Lanka, and the kingdom of Vengi in the north-west and south.
Krishnadevaraya was a powerful Vijayanagara Emperor who lived from 1471-1529 and led a large army in battles against the King of Bijapur.
King Shivaji was known as the 'Father of Indian Navy' for protecting his empire's coastline from various invaders including the Portuguese, British, Dutch, Siddis, and Mughals.