Theodosiopolis was conquered by the Umayyad general Abdallah ibn Abd al-Malik in 700/701.
It became the capital of the emirate of Ḳālīḳalā and was used as a base for raids into Byzantine territory.
Though only an island of Arab power within Christian Armenian-populated territory, the native population was generally a reliable client of the Caliph's governors.
As the power of the Caliphate declined, and the resurgence of Byzantium began, the local Armenian leaders preferred the city to be under the control of powerless Muslim emirs rather than powerful Byzantine emperors.

In 931, and again in 949, Byzantine forces led by Theophilos Kourkouas, grandfather of the future emperor John I Tzimiskes, captured Theodosiopolis.
Its Arab population was expelled and the city was resettled by Greeks and Armenians.
Emperor Basil II rebuilt the city and its defenses in 1018 with the help of the local Armenian population.
In 1071, after the decisive battle at Manzikert, the Seljuk Turks took possession of Theodosiopolis.
The Saltukids were rulers of an Anatolian beylik (principality) centered in Erzurum, who ruled from 1071 to 1202.
Melike Mama Hatun, sister of Nâsırüddin Muhammed, was the ruler between 1191 and 1200.

Theodosiopolis repelled many attacks and military campaigns by the Seljuks and Georgians (the latter knew the city as Karnu-Kalaki) until 1201 when the city and the province was conquered by the Seljuk sultan Süleymanshah II.
Erzen-Erzurum fell to the Mongol siege in 1242, and the city was looted and devastated.
After the fall of the Sultanate of Rum in early 14th century, it became an administrative province of the Ilkhanate, and later on the city was under Empire of Trebizond occupation for a while around the 1310s.
Then became part of the Çoban beylik, Black Sheep Turkmen, empire of Timur Lenk and White Sheep Turkmen.
It subsequently passed to Safavid Persia, until the Ottomans under Selim I in 1514 conquered it through the Battle of Chaldiran.
During the Ottoman Empire reign, the city served as the main base of Ottoman military power in the region.

It served as the capital of the eyalet of Erzurum.
Early in the seventeenth century, the province was threatened by Safavid Persia and a revolt by the province governor Abaza Mehmed Pasha.
This revolt was combined with Jelali Revolts (the uprising of the provincial musketeers called the Jelali), backed by Iran and lasted until 1628.
In 1733, the Iranian Nader Shah took Erzurum during the Ottoman–Persian War (1730–35), but if returned into Ottoman possession following his death in 1747.
Theodosiopolis was conquered by the Umayyad general Abdallah ibn Abd al-Malik in 700/701. It became the capital of the emirate of Ḳālīḳalā and was used as a base for raids into Byzantine territory. Though only an island of Arab power within Christian Armenian-populated territory, the native population was generally a reliable client of the Caliph's governors. As the power of the Caliphate declined, and the resurgence of Byzantium began, the local Armenian leaders preferred the city to be under the control of powerless Muslim emirs rather than powerful Byzantine emperors.
In 931, and again in 949, Byzantine forces led by Theophilos Kourkouas, grandfather of the future emperor John I Tzimiskes, captured Theodosiopolis. Its Arab population was expelled and the city was resettled by Greeks and Armenians. Emperor Basil II rebuilt the city and its defenses in 1018 with the help of the local Armenian population. In 1071, after the decisive battle at Manzikert, the Seljuk Turks took possession of Theodosiopolis. The Saltukids were rulers of an Anatolian beylik (principality) centered in Erzurum, who ruled from 1071 to 1202. Melike Mama Hatun, sister of Nâsırüddin Muhammed, was the ruler between 1191 and 1200.
Theodosiopolis repelled many attacks and military campaigns by the Seljuks and Georgians (the latter knew the city as Karnu-Kalaki) until 1201 when the city and the province was conquered by the Seljuk sultan Süleymanshah II. Erzen-Erzurum fell to the Mongol siege in 1242, and the city was looted and devastated. After the fall of the Sultanate of Rum in early 14th century, it became an administrative province of the Ilkhanate, and later on the city was under Empire of Trebizond occupation for a while around the 1310s. Then became part of the Çoban beylik, Black Sheep Turkmen, empire of Timur Lenk and White Sheep Turkmen. It subsequently passed to Safavid Persia, until the Ottomans under Selim I in 1514 conquered it through the Battle of Chaldiran. During the Ottoman Empire reign, the city served as the main base of Ottoman military power in the region.
It served as the capital of the eyalet of Erzurum. Early in the seventeenth century, the province was threatened by Safavid Persia and a revolt by the province governor Abaza Mehmed Pasha. This revolt was combined with Jelali Revolts (the uprising of the provincial musketeers called the Jelali), backed by Iran and lasted until 1628. In 1733, the Iranian Nader Shah took Erzurum during the Ottoman–Persian War (1730–35), but if returned into Ottoman possession following his death in 1747.
Erzurum