Abbi (also Abbio) was a Saxon warrior who fought alongside Widukind. He is mentioned in Carolingian annals for the year 785. He fled across the Elbe with Widukind, and after a peace was negotiated with Charlemagne in the Bardengau, Abbi and Widukind were both baptized. Abbi was probably closely related to Widukind, who was possibly his stepson or his brother in law.
References
Abbi (Saxon) Wikipedia(Text) CC BY-SA