The Ukraine conflict is an ongoing Interstate War known as the Russo-Ukrainian War, representing the largest conventional conflict in Europe since World War II. The conflict began in February 2014 with Russia's covert invasion and annexation of the Ukrainian peninsula of Crimea. This was followed by the War in Donbas, where Russia supported separatist armed groups in the Donetsk and Luhansk regions. The war's origins are rooted in Russia's desire to maintain a sphere of influence over former Soviet republics, its perception of NATO expansion as a security threat, and Ukraine's move toward European integration after the 2014 Revolution of Dignity.
The conflict operates in two main phases: the initial eight years of fighting in the Donbas region, which included the failed Minsk Agreements aimed at a ceasefire, and the major escalation to a full-scale invasion launched by Russia on February 24, 2022. This invasion, which Russia termed a "special military operation," is a clear violation of the United Nations Charter's prohibition on the use of force and the principle of territorial integrity. The war connects directly to the concept of great-power rivalry and has intensified the geopolitical competition between Russia, China, and the United States. A significant recent change occurred in September 2022, when Russia illegally annexed four Ukrainian oblasts—Donetsk, Luhansk, Kherson, and Zaporizhzhia—despite not fully controlling the territories.