[1] During World War I, the Imperial German Army occupied Sevastopol on 1 May 1918 despite the ongoing negotiations to reach the Treaty of Brest-Litovsk.

[1] During the Crimean campaign (1941–1942) of World War II, the Black Sea Fleet of the Soviet Navy was able to fend off the first air attack by the Nazi German Luftwaffe.

The ownership over Black Sea Fleet as well as its home base in Sevastopol became a subject of dispute between sovereign Russia and Ukraine.

In 1997, the Russian Federation and Ukraine signed the Partition Treaty on the Status and Conditions of the Black Sea Fleet which ended the dispute.

The lease arrangements were altered by the 2010 Kharkiv Pact, which tied a 30% reduction in the price of natural gas charged by Russia since 2009 to the continued occupation of the naval base until 2042.