Jannigo Prosstang was born on Concard Dawn and his family moved to Mandalore shortly after. He had a very close relationship with his cousin Ferrigo Prosstang. Rappretto Prosstang, Jannigo's father, was the brother of Q'osstigo Prosstang. In 52 BBY Jannigo and his cousin Ferrigo were sent off to be trained by the True Mandalorians. Jannigo was separated from his cousin to be trained by Montross. Due to Jannigo currently being the second oldest living member of the Rafrego Solus-Linnago Velrrus family line, he is the Chieftain's Arm of Clan Prosstang and handles many internal relations affairs of the clan, and leads the clan when designated in Ferrigo's absence.