The Mahabharata is the history of the Chandravansha (the Lunar dynasty), which originated with Soma, the Moon God. The son of Soma was Chandra. Chandra had a son called Pururava who ruled the kingdom of Prayaga, whose capital was located at Pratisthana. Pururava’s eldest son Āyu had a son called Nahusha. Nahusha married Viraja and they had six or seven sons. The second son was Yayati. According to another legend, Nahusha married Ashokasundari, the daughter of Shiva and Parvati, and she gave birth to Yayati and a hundred daughters.
Yayati had five sons: Yadu and Turvasu through his first wife Devayani, and Druhyu, Anu and Puru through his second wife Sharmishtha. When Yayati became old, he continued to lust for the pleasures of a youthful life. He summoned his five sons and asked them to temporarily loan him their youth. Four of the sons refused and they were cursed by Yayati that they would never be kings—this curse impacted the Yadava dynasty too, since one of Yayati’s five sons was Yadu. Puru, Yayati’s youngest son, agreed to loan his youth to his father. After enjoying the pleasures of the senses for a thousand years, Yayati returned to Puru his youth and made him the king. The lunar dynasty goes forward with Puru.
Puru’s son Duhshanta married Shakuntala and they had a son called Bharata (the founder of the empire called Bharatavarsha). Bharata had a grandson called Kuru, whose descendent Pratipa had a son called Shantanu. Shantanu married Satyavati and they had two sons, Chitrangada and Vichitravirya. Krishna Dvaipayana (Veda Vyasa) was already born through a union between Sage Parashara and Satyavati. A union between Shantanu and Ganga had already resulted in the birth of the powerful warrior Bhishma. Krishna Dvaipayana fathered Dhristarashtra on Vichitravirya’s first wife Ambika, and Pandu on Vichitravirya’s second wife Ambalika. He also fathered a son called Vidura on Vichitravirya’s maid.
The hundred Kourava brothers were the sons of Dhristarashtra, and the five Pandava bothers were the acknowledged sons of Pandu. Since Kuru was the common ancestor of both the Kouravas and the Pandavas—in terms of bloodline, the five Pandava brothers too were Kouravas. Krishna was born in the Yadava branch of the Lunar dynasty.