Although a Brahmin lineage, this gotra is descended from Kshatriya prince of the Suryavansha dynasty who was the great grandson of legendary King Mandhatra. Mandhatra was killed by Lavanasura who was killed later by Rama's brother Shatrughna. This is one of ancient India's most prominent and famous lineages, having produced Rama and his 3 brothers (See Genealogy of Rama) and Yadava lineage from Ikshvaku King Haryaswa in which Krishna was born. Jayadratha of Mahabharata also belonged to solar line. The first notable king of the dynasty was Ikshvaku. Other Brahmin gotras from solar line are Vatula, Shatamarshana, Kutsa, Bhadrayana and Vishnuvriddha. Of these Kutsa and Shatamarshana also descend from King Mandhatra like Harita gotra and have either Mandhatra or his sons (Ambarish/Purukutsa) as part of their Pravaras. The Puranas, a series of Hindu mythological texts, document the story of this dynasty. Harita was separated from Ikshvaku by twenty-first generations. To this day, many Kshatriyas claim descent from the Suryavanshi dynasty to substantiate their claims to royalty.
Brahmins of the Harita gotra trace their lineage to the eponymous prince. While most Brahmins claim to be descended from ancient sages, those of the Harita gotra claim to be descended from Kshatriyas trained by the Brahmin Angirasa and hence they have full kshatriya qualities. This created, according to the Linga Purana, "Brahmins with the qualities of Kshatriyas". Harita lived around 500 BCE. Dharmsutra of Harita are dated to a period of c. 300 BCE.
This is recorded in the Hindu tradition in the Vishnu Purana:
Ambarishasya Mandhdtus tanayasya Yuvanasvah putro bhut tasmad Harito yato ngiraso Haritah. "The son of Ambarisha, son of Mandhatri was Yuvanasva From him sprang Harita from whom the Harita Angirases were descended."
and in the Linga Purana:
Harito Yuvanasvasya Harita yata atmajah ete hy Angirasah pakshe kshattropeta dvijatayah. "The son of Yuvanasva was Harita of whom the Haritash were sons". "They were on the side of Angiras twice born men." "Brahmans of Kshattriya lineage." 
and in the Vayu Purana:
The Pravara of this gotra, used in ceremonies to reference the ancestors of the participant Brahmin has 2 variations:
Sage Harita, son of Chyavana, wrote the Harita Smriti, a work of law, and taught his student, Bappa Rawal of Guhilot (later to be called Sisodia) martial arts and the four cardinal duties for the service of the state:
- To follow the principles of Manav Dharma (the Religion of Man) and preserve Vedic Culture.
- To serve all God's Creations as a service to God, the Creator of all life.
- To endeavour constantly to keep the human soul awakened and alive, in order that human beings would value the Dignity of Man.
- To help recognise Man's special status in the hierarchy of God's creations-the eternal principles underlying cosmic creation.
The story of how he became a brahmin
Once there lived a great King named Haritha; he was the grandson of King Ambareesha, who is an ancestor of Sri Rama.
Once he was passing by a dense forest where he hears the shrill moaning of a cow. He goes in the direction where the voice was coming; he sees that a tiger has caught the cow and was about to kill the cow.
Since he is a Kshatriya and a king, he feels that it is his duty to protect the weak, and that there is no sin in killing the tiger. He aims at the tiger. Meanwhile, the tiger also thinks it should do something that the king also suffers and with that it kills the cow and King Haritha kills the tiger.
Since he has witnessed the Go Hatya(Death of sacred cow) taking place, the king is affected by the Go Hathi Dosham (sin). He gets worried, when suddenly he hears an Asareeri (Divine Voice) which asks him to proceed to Sathyavratha Kshetram and to take bath in Ananthah Sarasu and worship Lord Adhi Keshava, whereby his sins will vanish.
King Harita goes back to Ayodhya and consults Vashishta Maharishi, who tells him about the Sriperumpudur Mahatyam and narrates how the Bhootha Ganas (those who serve Lord Shiva in Shiv Lok) got rid of their Saapam (curse) there,and also the route to that place. King Haritha then makes alternative arrangement to run the kingdom and proceeds to Sriperumpudur (near Chennai, Tamil Nadu).
He takes bath in Ananthah Sarasu and prays to Lord Adhi Kesava; after a while the merciful lord appears before Haritha Maharaja and instructs him on all the Mantras which would help in getting rid of the Dosham. He also says that though all these years he was a Kshtriya, due to his blessings he has now become a Brahmin, and henceforth his descendants will also be Brahmins (even today his descendants are known as Brahmins of Haritha Gothra). The Lord also gives Upadesham of all Mantras to him. Haritha Maharaja rebuilds the Adhi Kesava temple, and performs consecration of the temple on an auspicious day. 
- K. Jamanadas (2007). Devadasis: Ancient to Modern. Kalpaz Publications. p. 64.
- Bella Vivante (2007) . Women's Roles in Ancient Civilizations: A Reference Guide. Greenwood Press. p. 64. ISBN 0313301271.
- Classical Dictionary of Hindu Mythology and Religion, Geography, History, and Literature by John Dowson