The Battle of Jajau was fought between the two Mughal princes and brothers Bahadur Shah I and Muhammad Azam Shah on 20 June 1707. In 1707, their father Aurangzeb died without having declared a successor; instead leaving a will in which he instructed his sons to divide the kingdom between themselves. Their failure to reach a satisfactory agreement led to a military conflict. After Azam Shah and his three sons were killed in the Battle of Jajau, Bahadur Shah was crowned as the Mughal emperor on 19 June 1707 at the age of 63.

After a 49-year reign, the Mughal emperor Aurangzeb died in 1707 without officially declaring a crown prince. He left a will advising his sons to divide the empire between themselves.

At the time of Aurangzeb's death, his eldest son, Bahadur Shah I, was stationed at Jamrud, 12 miles west of Peshawar. His second son, Muhammad Azam Shah, was stationed at Ahmednagar, east of Bombay. With the distance between Jamrud and Agra being 715 miles and the distance between Ahmednagar and Agra being 700 miles, whoever reached the capital city of Agra first would capture the Mughal throne.

Even before Aurangzeb died, Bahadur Shah I had made preparations for a battle for the Mughal throne. With the help of Munim Khan, the naib subahdar of Lahore, he gathered troops from local rulers in Beas and Satluj. He had built bridges and improved the roads between Lahore and Peshawar. He was also successful in persuading Rao Budh Singh (the king of Bundi) and Bijai Singh of Kachhwa to send their soldiers to him.

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