A civil strife between the Christian reiks Fritigern and the pagan reiks Athanaric prompted Roman military intervention on the side of the Christian party, leading to the Gothic War (376–382).
When the Gothic leader Fritigern demanded hostages to secure peace from the Romans he volunteered and departed the Roman camp to bring the other hostages safely to Fritigern, but before he arrived some elements of the two armies got out of control and engaged, starting the famous Battle of Adrianople.
They end the civil war, and Fritigern converts to Christianity.