The Great Emperor Raghu (Sanskrit: रघु) was a valorous king of the Ikshvaku dynasty. According to the Raghuvamsha, he was born to king Dilipa and his queen Sudakshina. His name in Sanskrit means the fast one, deriving from Raghu's chariot driving abilities. So celebrated were the exploits of Raghu, that his dynasty itself came to be known as the Raghuvamsha or the Raghukula after him. The history of his dynasty is elaborated upon by Kalidasa in his Raghuvamsha.

A number of Puranas, which include the Vishnu Purana, the Vayu Purana, the Linga Purana, mention Dirghabahu as the son of Dilipa and Raghu as the son of Dirghabahu. But the Harivamsha, the Brahma Purana and the Shiva Purana mention Raghu as son of Dilipa and Dirghavahu as his epithet. The lineage described in the Raghuvamsha mention Dilipa as the father of Raghu. According to most of the Puaranas, as well as Kalidasa, Raghu was succeeded by his son Aja, who was the father of Dasharatha, the father of Rama, Lakshmana, Bharata and Shatrughna.