Enzeli Operation
1920 CE.
Shown on the map at 37.467°, 49.467°.
The Anzali Operation was a naval and amphibious action carried by the Soviet Caspian Flotilla during the Russian Civil War. The target was the White Russian Caspian Flotilla interned at Anzali, Iran, which was under the custody of the British North Persian Force. The British troops were surrounded and forced to capitulate, while the flotilla was captured by the Soviets.
Text from the Wikipedia article Anzali Operation, licensed CC BY-SA 4.0.