The Battle of Derbent was fought in 1032 between the defending forces of Lekia and Emirates of Derbent against the invading force of Alans and Sarir. The battle occurred after the invaders raided Shirvan and were on their way back north with captives and booty, they were intercepted at Derbent by forces led by the emir Mansur Ibn Maymun, who attacked them in the passes and recovered the booty taken from Shirvan.
Background
During the 11th century Shirvan and Derbent were involved in a struggle for influence in the eastern Caucasus. The emir of Derbent Mansur ibn Maymun had previously been driven from the city and later returned with the assistance of the ruler of Sarir. Mansur subsequently maintained close relations with Sarir, including through his marriage to a daughter of its ruler.
In 1032, an invading force entered Shirvan. According to the Shirvan section of "History of Shirvan and al-Bab," the attackers included Rus', Alans and Saririans. They captured and plundered Yazidiyya (modern Shamakhi) and other parts of Shirvan before beginning their withdrawal northward.
Battle
After plundering Shirvan, the invading army began return northwards, when the armt reached Derbent the people of the frontier district (Al-Bab) attacked the forces
the defenders blocked the roads and mountain passes and inflicted a heavy defeat on the invaders. The chronicle states that many of the attackers were killed and that the defenders recovered the Muslim property including people and goods that had been carried away from Shirvan.
Only a small part of the invading force escaped. Among the survivors was the ruler of the Alans, who returned the following year seeking revenge.
Aftermath
In 1033 the ruler of Alania returned with intentions of revenge on Derbent. The rus Alans advanced towards Derbent but were defeated on the way in the Battle of Al-Qarakh (generally identified as modern Urkarakh in Dagestan) by the defending force of the Lezgin and Dargin inhabitants of the city.