Qajar Iran and the Ottoman Empire determine their international boundary in the second treaty of Erzurum.

The Guarded Domains of Iran, commonly known as Qajar Iran, was the Iranian state under the rule of the Qajar dynasty, which lasted from 1789 to 1925. It was founded by Agha Mohammad Khan, a chieftain of the Qajar tribe, a Turkic tribe based in northern Iran. In the power struggle following the death of Karim Khan Zand in 1779, Agha Mohammad defeated all competitors from the preceding Zand and Afsharid dynasties, unifying Iran. He re-asserted Iranian sovereignty over large parts of the Caucasus and was formally crowned as Shah in 1796. Although he was murdered the next year, he was succeeded by his nephew Fath-Ali Shah, and the Qajars maintained control over the country until their deposal in 1925.