Son of sage Richika and Satyavati, daughter of king Gadhi.
Married with Renuka. They had five sons, one of them was Parashurama, the sixth Avatar of Vishnu.
Jamadagni was killed by Kartavirya Arjuna, because he did not give him his wish fulfilling cow. Parashurama avenged his father by eradicating the warrior caste (kshatriyas).
Read about Jamadagni here