WHY DID THE RUSSIAN FEDERATION ANNEX THE CRIMEAN PENINSULA AND INVADE THE DONBAS IN EASTERN UKRAINE IN 2014?

The research discusses Russia's aggression against Ukraine in 2014 and seeks to find the explanatory answer to this question: Why did the Russian Federation illegally annex the Crimean Peninsula from Ukraine and invade Donbas in 2014? The thesis studies and evaluates Russia's hostilities toward Ukraine within the lenses of three hypothetical explanations'realist, constructivist, and regime survival'in two case studies: 1) annexation of the Crimean Peninsula from Ukraine and 2) invasion of Ukraine's Donbas regions. The study finds that despite both cases occurring sequentially, the causal factors that prompted Russia toward aggression in Crimea and Donbas are different. The thesis argues that material factors are important and stay in the background of Russia's decisions in both cases. They were not necessarily the most significant aspect in the case of Crimea's annexation, but they were a factor in the case of Donbas's invasion. However, cultural and ideational factors mattered most in both case studies. Besides, the research points out the importance of considering Russia's internal domestic factors, which refer to the Kremlin's regime survival. The latter has more explanatory power in the case of Crimea's annexation. Consequently, the understanding of Russia's motives in both case studies provides important background for the further development of Ukraine-Russia relations and sheds light on the prospects of conflict termination between two states.