In February 2014, Russia launched a covert offensive to seize control of Ukraine’s Crimean Peninsula, culminating in the peninsula’s annexation by Russia in March 2014. This operation — spearheaded by armed men without insignia later dubbed “little green men” — was swift and largely bloodless, but it violated international law and sparked global condemnation. Drawing on investigative reports and international organizations’ findings, this article examines the timeline of the Crimea takeover, the tactics used by Russian forces, the role of the “little green men,” the responses of Ukraine and the international community, the breach of international law, and the long-term consequences of the annexation.