The province is believed to be as old as the Achaemenid era (ca.
550–330 BCE).
It is mentioned in the Avesta, where prophet Zoroaster was born by the river Aras and wrote his book in the Sabalan Mountains.
During the Parthian era, the city had special importance among the cities of Azerbaijan.
Some Muslim historians attribute the foundation of Ardabil to the king Peroz I of the Sassanid Empire.
The Persian poet Ferdowsi also credits the foundation of the city to Peroz I. Ardabil suffered some damages caused by occasional raids of Huns from the 4th to 6th century CE.
Peroz repaired those damages and fortified the city.
Peroz made Ardabil the residence of provincial governor (Marzban) of Azarbaijan.

Due to its proximity to the Caucasus, Ardabil was always vulnerable to invasions and attacks by the mountain peoples of the Caucasus as well as by the steppe dwellers of South Russia past the mountains.
In 730–731, the Khazars managed to get past the Alan Gates, defeated and killed the Arab governor of Armenia named Al-Jarrah ibn Abdallah on the plain outside the town of Ardabil, and subsequently captured the town, as they continued their conquests.

During the Islamic conquest of Iran, Ardabil was the largest city in north-western Iran, ahead of Derbent, and remained so until the Mongol invasion period.
Ardabilis fought the Mongols three times; however, the city fell after the third attempt by Mongols, who massacred the Ardabilis.
Incursions of Mongols and subsequently the Georgians, who, under Tamar the Great, captured and sacked the city with some 12,000 citizens reputedly killed, devastated the city.
The city however recovered and was in a more blossoming state than before, though by this time the principal city in the Azerbaijan region had become Tabriz, and under the later Ilkhanate, it had become Soltaniyeh.

Safavid king Ismail I, born in Ardabil, started his campaign to nationalize Iran's government and land from there, but consequently announced Tabriz as his capital in 1501.
Yet Ardabil remained an important city both politically and economically until modern times.
During the frequent Ottoman-Persian Wars, being close to the borders, it was often sacked by the Ottomans between 1514 and 1722 as well as in 1915 during World War I when the former invaded neighboring Iran.

In the early Qajar period, crown prince Abbas Mirza, son of then incumbent king (shah) Fath Ali Shah Qajar (r. 1797–1834) was the governor of Ardabil.
With Ardabil already once being sacked by the Russians during the Russo-Persian War of 1804–1813, and this being the era of the Russians steadily advancing into the Iranian possessions in the Caucasus, Abbas Mirza ordered the Napoleonic general Gardane, who served the Qajars at the time, to strengthen and fortify the town with ramparts.
During the next and final war, the Russo-Persian War of 1826–28, the ramparts were stormed by the Russian troops, who then temporarily occupied the town.
The town's extensive and noted library, known as the library of Safi-ad-din Ardabili, was taken to St. Petersburg by General Ivan Paskevich with the promise that its holdings would be brought to the Russian capital for safekeeping until they could be returned, a promise never fulfilled.

After the Russo-Persian Wars, Iran ceded its territories in the Caucasus to Russia under the terms of the Treaty of Turkmenchay (1828).
As a result, Ardabil was situated only 40 kilometers from the newly drawn border, becoming even more important economically as a stop on a major caravan route along which European goods entered Iran from Russia.
After he visited Ardabil in 1872, German diplomat Max von Thielmann noted, in his book published in 1875, the extensive activity in the town's bazaar, as well as the presence of many foreigners, and estimated its population at 20,000.
During the early Iranian Constitutional Revolution, Russia occupied Ardabil together with the rest of Iranian Azerbaijan until the eventual collapse of the Russian Empire in 1917.
The province is believed to be as old as the Achaemenid era (ca. 550–330 BCE). It is mentioned in the Avesta, where prophet Zoroaster was born by the river Aras and wrote his book in the Sabalan Mountains. During the Parthian era, the city had special importance among the cities of Azerbaijan. Some Muslim historians attribute the foundation of Ardabil to the king Peroz I of the Sassanid Empire. The Persian poet Ferdowsi also credits the foundation of the city to Peroz I. Ardabil suffered some damages caused by occasional raids of Huns from the 4th to 6th century CE. Peroz repaired those damages and fortified the city. Peroz made Ardabil the residence of provincial governor (Marzban) of Azarbaijan.
Due to its proximity to the Caucasus, Ardabil was always vulnerable to invasions and attacks by the mountain peoples of the Caucasus as well as by the steppe dwellers of South Russia past the mountains. In 730–731, the Khazars managed to get past the Alan Gates, defeated and killed the Arab governor of Armenia named Al-Jarrah ibn Abdallah on the plain outside the town of Ardabil, and subsequently captured the town, as they continued their conquests.
During the Islamic conquest of Iran, Ardabil was the largest city in north-western Iran, ahead of Derbent, and remained so until the Mongol invasion period. Ardabilis fought the Mongols three times; however, the city fell after the third attempt by Mongols, who massacred the Ardabilis. Incursions of Mongols and subsequently the Georgians, who, under Tamar the Great, captured and sacked the city with some 12,000 citizens reputedly killed, devastated the city. The city however recovered and was in a more blossoming state than before, though by this time the principal city in the Azerbaijan region had become Tabriz, and under the later Ilkhanate, it had become Soltaniyeh. 
Safavid king Ismail I, born in Ardabil, started his campaign to nationalize Iran's government and land from there, but consequently announced Tabriz as his capital in 1501. Yet Ardabil remained an important city both politically and economically until modern times. During the frequent Ottoman-Persian Wars, being close to the borders, it was often sacked by the Ottomans between 1514 and 1722 as well as in 1915 during World War I when the former invaded neighboring Iran.
In the early Qajar period, crown prince Abbas Mirza, son of then incumbent king (shah) Fath Ali Shah Qajar (r. 1797–1834) was the governor of Ardabil. With Ardabil already once being sacked by the Russians during the Russo-Persian War of 1804–1813, and this being the era of the Russians steadily advancing into the Iranian possessions in the Caucasus, Abbas Mirza ordered the Napoleonic general Gardane, who served the Qajars at the time, to strengthen and fortify the town with ramparts. During the next and final war, the Russo-Persian War of 1826–28, the ramparts were stormed by the Russian troops, who then temporarily occupied the town. The town's extensive and noted library, known as the library of Safi-ad-din Ardabili, was taken to St. Petersburg by General Ivan Paskevich with the promise that its holdings would be brought to the Russian capital for safekeeping until they could be returned, a promise never fulfilled.
After the Russo-Persian Wars, Iran ceded its territories in the Caucasus to Russia under the terms of the Treaty of Turkmenchay (1828). As a result, Ardabil was situated only 40 kilometers from the newly drawn border, becoming even more important economically as a stop on a major caravan route along which European goods entered Iran from Russia. After he visited Ardabil in 1872, German diplomat Max von Thielmann noted, in his book published in 1875, the extensive activity in the town's bazaar, as well as the presence of many foreigners, and estimated its population at 20,000. During the early Iranian Constitutional Revolution, Russia occupied Ardabil together with the rest of Iranian Azerbaijan until the eventual collapse of the Russian Empire in 1917.
Ardabil