The Battle of the Aqsu River, also known as the Battle of Chaghan Mürän was fought between the forces of the Golden Horde and the Ilkhanate during the second phase of the Berke–Hulegu war. The Jochid general Nogai set out with a large army through Derbent, and the Ilkhanate ruler Abaqa Khan sent his brother Yoshmut with an army to confront him.
Background
Relations between the Golden Horde, ruled by Berke Khan, and the Ilkhanate, founded by Hulegu Khan, deteriorated in the 1260s. A key source of tension was religious and political rivalry, as Berke had converted to Islam and opposed Hulegu’s campaigns in the Middle East, particularly the destruction of Baghdad in 1258. Following Berke’s reign, this hostility continued under his successors, while the Ilkhanate was consolidated under Abaqa Khan after Hulegu’s death in 1265.
During this period, both sides engaged in raids and military movements along the frontier regions of the Caucasus. Control of strategic passes such as Derbent became especially important, as they connected the northern steppe territories of the Golden Horde with the southern domains of the Ilkhanate. These border clashes escalated into a series of engagements, including the campaign led by the Golden Horde general Nogai, which ultimately resulted in the confrontation at the Aqsu River.
Battle
An army under Abaqa Khan’s brother, Yoshmut, met Nogai on the Aqsu River just north of Shirvan. Battle lines were drawn, and fighting began; both armies suffered heavy losses. Ta'achar Aqa’s father, Qutu-Buqa, fought valiantly until he was killed. Nogai too suffered an arrow wound to the eye. His army was defeated and withdrew to Shirvan. Meanwhile, both Abaqa Khan and Berke Khan arrived with large reinforcements, forming on opposite banks of the Kura River, and for 14 days arrows were exchanged. Berke grew frustrated and marched towards the Georgian capital of Tbilisi in order to find a crossing; however, he fell ill and died along the route, leaving his empire without a khan. His coffin was taken to Sarai and buried, while his army withdrew.
Aftermath
Abaqa did not pursue them and instead built a wall along the other side of the Kura River, with deep trenches dug. A division of Mongols and Muslims was stationed there to keep guard. Caravans, however, continued to pass on both sides.