Humayun was the second Mughal ruler of territories in the Indian subcontinent including what is now Afghanistan, Pakistan, and parts of northern India. He was the son and successor of Babur, the founder of the Mughal dynasty. He became the Mughal emperor at the age of 23. He was inexperienced at the time of ascending to the throne and faced bitter rivalry from his half-brother Kamran Mirza who ruled over Kabul and Lahore. Even though Humayun was a brave soul and an adventurous ruler, he lost several territories to his rivals over the ensuing years. However, he was not someone to accept defeat so easily and he successfully won back his territories after a few years. Many years of his reign were spent in defending territories from his rivals, and he was even forced to seek refuge in Persia for some time. When he returned to his kingdom as the undisputed Mughal leader after the death of his rivals, he set about consolidating the empire for the generation to come. He embarked on several campaigns to expand the Mughal territories and at the time of his death, the Mughal Empire spanned almost one million square kilometers. Even though not counted amongst the greatest Mughal emperors, Humayun ensured that he left behind a rich legacy for his son Akbar.