After the death of the Iberian Kuropalates David in 1000, the troops of Emperor Basil II occupied the castles and towns in the region of Tao-Tayk‛, which included Oltu.

[5] In the following centuries, Oltu successively passed into the control of the Seljuk Turks, the Mongols and Turkmen tribes.

[6] In the summer of 1829, the Russian Empire took control of the region, but ultimately relinquished it to the Ottomans upon the conclusion of peace.

[4] The Olti Okrug along with the entire Kars Oblast were ceded by the Russian SFSR to the Ottoman Empire by virtue of the Treaty of Brest-Litovsk in 1918.

The First Republic of Armenia with British support expanded to include the self-governing Kars Oblast in the wake of the power vacuum caused by the Russian Revolution, however, was prevented from occupying the western half of the Olti Okrug by the commander of the Black Sea, G.F. Milne, as he believed Armenia had already acquired more territory than they could handle.

[5] Atop the north tower are the remains of a Georgian hexaconch church in which a fragment of a 7th-century “bilingual” Greek-Armenian inscription was reused in the foundation.

[5][10] Late-antique and medieval churches as well as fortresses are located in the hills surrounding the Oltu-Penek valley at Cücürüs, Körolu, Olur, Kamhis, Sağoman, Olan, and nearby Kız.

[14] In 1914, the town of Oltu had a population of 3,258, two thirds of whom were Armenians, with the remainder consisting of Turks, Russians, and Roma people among others.