This article is missing information about the detailed causes of the 1821–23 Ottoman–Persian War(s). Please expand the article to include this information. Further details may exist on the talk page.(August 2016)
Crown Prince Abbas Mirza of Persia, at the instigation of the Russian Empire, invaded Western Armenia and the areas surrounding Iranian Azerbaijan. The governor of Baghdad's invasion of Persia is defeated by Mohammed Ali Mirza who then besieges Baghdad, his untimely death ends the siege. Meanwhile, Abbas Mirza marched into eastern Anatolia with 30,000 troops and met an Ottoman army of 50,000 at the Battle of Erzurum. Abbas Mirza scored a crushing defeat over the Ottomans despite being severely outnumbered and his army suffering from a cholera epidemic.
Thanks to the recent modernisations, the so-called "Nezam-i-Jadid" reforms of the Persian army according latest European model made possible by Abbas Mirza's brother, Dowlatshah, it made the army qualitatively far superior over that of their Ottoman Turkish archrivals, despite being severely outnumbered.
Peace was not concluded until the Treaty of Erzurum two years later; both sides recognized the previous borders, with no territorial changes. Also included in the treaty, was the guaranteed access for Persian pilgrims to holy sites within the Ottoman Empire.