In March 2014, Crimea held a disputed 'referendum' on joining Russia, claiming an 83.1% voter turnout with 96.77% in favor of the union. This event was framed as part of the response from Russia and the Russian-speaking population in Crimea to the upheaval in Ukraine that year. The situation was exacerbated by rising separatist sentiments on the peninsula, significantly influenced by the presence of unmarked Russian troops.

By the afternoon of March 2, 2014, U.S. intelligence reported that the Russian military had taken control of all strategically important sites in Crimea. Approximately 15,000 Russian soldiers had been deployed, occupying airfields and ports, effectively blocking roads and rendering Ukrainian border guard and military units inoperable. Ukrainian officials and military personnel faced intense pressure to abandon their posts and pledge allegiance to pro-Russian forces, leading to a passive resistance strategy from the Ukrainian military as ordered from higher command.

The Crimean referendum, widely criticized by the international community, raised significant geopolitical tensions and set the stage for ongoing conflicts between Russia and Ukraine, altering the balance of power in Eastern Europe. The event is often cited as a turning point that led to the annexation of Crimea by Russia, further complicating relations in the region and resulting in severe economic sanctions against Moscow.