The Battle of the River Thatis was part of a succession dispute in the Bosporan Kingdom that was fought out during 310/309 BC.
His brother Eumelus disputed Satyros II's right to the throne and gathered an army with his allies, the Siraces tribe.
The defeat was not decisive: Eumelus and his allies escaped to the capital city of the Siraces, which was situated along the River Thatis.
His eldest son Satyrus succeeded him as king, but his younger brothers Eumelus and Prytanis contended with him for the throne.
He pursued to kill the fleeing troops, but stopped when he heard that his brother Eumelus was winning on his right wing and that his own mercenaries had fled.
[5] Aripharnes and Eumelus managed to escape to the capital city of the Siraces, Siracena, which was located on the Thatis River.
He suffered many casualties in an unsuccessful attempt to take the entrance through the castle, but he managed to defeat the defenders at the entry through the swamp.
[6] After crossing the river, Satyrus began to cut down the woods to clear the route for an attack on the city's walls.