Wrangel overprint on a Levant overprint on a standard 1917 stamp.
From the second half of the 19th century, Russia opened additional postal offices in a number of foreign countries, including the island of Crete, China, Mongolia, the Ottoman Empire, Romania, and Bulgaria. To pay for postal services at these offices, stamps of the Russian Empire or specially produced postage stamps were used. Postage stamps were issued, in particular, for the Russian post in the Ottoman Empire ("Russian Levant"), in China, and on the island of Crete.
The Russian Empire maintained foreign post offices for forwarding correspondence for various reasons, similarly to other major powers of its time.
By the end of 1920, all Russian foreign post offices had ceased to exist.
General Wrangel's Army, or the Russian Army, was a formation of White forces in the South of Russia during the Civil War. The Russian Army was formed under General Wrangel's command in April 1920, after the defeat of the Armed Forces of South Russia in Crimea, and existed until the November 1920 evacuation of the White forces from Crimea.
In August to October 1920, the administration of General Wrangel in Crimea issued Russian Empire stamps with overprints: a new value (in three lines); "South of Russia" and a new value.
In 1920-1921 in Constantinople (Turkey), stamps were issued with overprints: "Post of the Russian Army" and a new denomination on stamps of the Russian Empire, the Russian Levant, and stamps of the Denikin issue; "Russian Post" and a new denomination on stamps of the Russian Empire, the Russian Levant, and Ukraine, as commercial issues.