Akhsu (Azerb. Ağsu) is a city and the administrative center of the Akhsu region of Azerbaijan, located on the Akhsu River, 35 km northeast of the Kurdamir railway station.

History
A. A. Bakikhanov in his book notes that in 1735 Nadir Shah resettled the population of Shamakhi to the new city he founded, located on the banks of the Akhsu River. At present, the name of the city of Akhsu, which is a regional center, is indicated in some sources as New Shamakhi. This is due to the resettlement of the population of Shamakhi to Akhsu. Since that time, the historical city of Shamakhi was called Old Shamakhi, and Akhsu – New Shamakhi. The name of the city that existed in the 18th century was taken from the name “Ahsuchay” and in many sources the city was called Akhsu. The ruins of the city of Agsu “Kharaba sheher” (Ruined City), which preserved the history of the 18th century, are located in the south of the modern city of Agkhsu.
S. Bronevsky notes that the surroundings of the city were surrounded by fortified walls. The fortress had towers of a quadrangular and round shape. A deep ditch was dug in front of the fortress walls, and the lower part of the buildings for housing consisted of cellars. The upper part of the buildings collapsed into the basement. The existing pits are the remains of basements. Residential buildings in the city were located very closely. The streets were very narrow. This created difficulties for movement on wagons. Undoubtedly, the central streets of the city were relatively wide.
On the site of the city of Akhsu, samples of simple pottery dating back to the Middle Ages and a copper coin minted in honor of Surkhay Khan were found. The coin belongs to the period before the issuance of the order of Nadir Shah on the founding of the city. This fact strengthens the hypothesis about the emergence of the city of Akhsu on the basis of the village of Akhsu. Some historical primary sources provide information about Akhsu as a center of trade and handicrafts in the 16th-18th centuries. At the same time, during the primary excavations carried out in Kharaba sheher, materials were found dating back to the period before the conquest of Shamakhi by Nadir Shah, namely 100-150 years ago. It is possible that after Nadir Shah moved the population of Shamakhi to the village located on the banks of the Akhsuchay, additional construction work was carried out. In the 18th century, there were strong fortress walls and defensive fortifications in the city of Agsu. The city continued to develop and XVIII century turned into one of the largest cities of Azerbaijan with a large population.

V. Levyatov notes that at the end of the 18th century the population of New Shamakhi (Akhsu) reached about 10 thousand people, while the population of Ganja, Ardabil, Shushi, Nukha, Baku and other cities was no more than 3-8 thousand. S. Elizarov writes that 15,510 manats of tax were collected from the population of Akhsu in favor of Shirvan Khan. This fact indicates that a heavy tax system was applied in the city. The city of Ahsu at the end of the Middle Ages played an important role in the socio-political and military life of Azerbaijan.
In the summer of 1737, Nadir Shah sent his army to Shamakhi. Despite the fact that Surkhay Khan left the city, the people of Shamakhi held the line for two months. Enraged by this, Nadir Shah at the end of August 1734, after the capture of Shamakhi, burned and destroyed the city, then gave the order to resettle the inhabitants of the city. At the end of May 1735, Nadir Shah issued an order to build a new city on the banks of the Akhsuchay. After the completion of construction work, the entire population of Shamakhi settled here, and the residence of the Shirvan rulers was also moved here.
In 1743, an uprising broke out in Shirvan against the oppression of Nadir Shah. At that time, false princes appeared on the arena – Sam Mirza I, II, III, who considered themselves descendants of the Safavids, two of them acted in Shirvan. With the support of Surkhay Khan, Sam Mirza I conquered New Shamakhi (Akhsu) with 50,000 troops. The population, exhausted under the yoke of Nadir Shah, met him with respect. He freed the people from taxes imposed by Nadir Shah. However, during the battle on the Shirvan plain between the son of Nadir Shah Nasrullah Mirza and Mirza I himself, the latter was killed.

In October 1743, Mirza II himself, with the support of Surkhay Khan’s son Muhammad, played an important role in raising a major uprising in Shirvan. The population of Akhsu expelled the Iranian governors. However, after three defeats, Nasrullah Mirza was finally able to capture the Akhsu fortress with cannon fire. It was the first blow to the developing city. The source indicates that the Persians surrounded the city. A small number of inhabitants remained in the city, a few days after the capture of the city, the population was completely destroyed. Nadir Shah called this day as “Allah dad” (God help). After the death of Nadir Shah in 1747, independent khanates appeared on the ground, one of them was Shirvan Khanate. The Shirvan Khanate (in 1747-1763) was dominated by dual power.
During this period, there was a struggle between local feudal lords for dominance in the region. Under these conditions, in 1755, the Sheki Khan Haji Chelebi surrounded Ahsu. In the battle for Akhsu, Haji Celebi suffered heavy losses and was forced to retreat. Hussein Ali Khan, not accepting the keys to the gates of the city of Akhsu from Haji Muhammad Ali Khan, returned to his khanate. In 1762, the population of the city of Akhsu suffered greatly from the plague epidemic that spread throughout the Transcaucasus. In 1763, Akhsu and Shamakhi united in a single khanate (A. A. Bakikhanov refers this event to 1765). Muhammad Said Khan and Aghasi Khan, having captured Akhsu, killed Haji Muhammad Ali. The capital was moved from Akhsu to Shamakhi. In 1767, the Cuban Khan Fatali Khan and the Sheki Khan Hussein Khan united and surrounded Shemakha from two sides. Aghasi Khan, together with Muhammad Said Khan, could not resist. As a result, the capital was again moved to Ahsu. Both khans appointed their deputies to manage the city. The Shirvan regions of Serderin and Gasan joined the Sheki Khanate, and the rest – to the Quba.
In July 1769, after the defeat of the city of Akhsu by the Cuban Khan Fatali Khan, the population was resettled in Shamakhi. According to sources, in a short time, the entire population of Aesu settled in Shamakhi. S. Gmel writes that when he was in Akhsu, he saw nothing but the destroyed walls. The written sources of travelers M. Biberstein, S. Bronevsky and other authors indicate that during the forced relocation of people from Akhsu to Shamakhi, the population decreased so much that some streets remained empty. And in subsequent years, the city of Ahsu was repeatedly attacked. In 1795, during Agha Mohammed Shah’s campaign against Azerbaijan, part of the population fled to Cuba and other provinces, and those who could not were destroyed. Thus, the city of Ahsu founded by Nadir Shah was destroyed by Agha Mohammed Shah Qajar.
In the 18th century, the city of Akhsu repeatedly fell victim to feudal raids. Frequent relocations, destruction dealt a blow to the hopes of residents to settle in this city. For this reason, the inhabitants of the city did not strive to build beautiful houses, mosques, baths, tombs, public and official buildings. In the sources of the beginning of the 19th century, you can often find the name of the city, but in Akhsu is mentioned very rarely at the end of the century. Until 1967, Akhsu was an urban-type settlement, in 1967 it received the status of a city.
On October 8, 1943, Akhsu began to exist as an administrative-territorial region.

Economy
In Soviet times, a dairy plant and an asphalt plant were built in the city.