King Babar, the founder of the Mughal Empire, did not have a surname. He was simply known as Babar, which is a Persian word meaning "tiger".
While many rulers in the Mughal Empire adopted surnames, Babar did not. His descendants, however, adopted surnames like Timurid, Mughal, and Shah Jahan.
The name "Babar" itself was a title, signifying his strength and courage.