In the decades following the collapse of the Soviet Union in 1991, Ukraine moved toward closer integration with Europe. When pro-Russian Ukrainian Pres. Viktor Yanukovych tried to reverse that trend in 2014, protests swept him from power. Having lost an ally, Vladimir Putin invaded and annexed the Ukrainian autonomous republic of Crimea. He also provoked separatist uprisings in Donetsk and Luhansk, two regions in eastern Ukraine; fighting between pro-Russian militias and the Ukrainian government continued there for years. Running on a populist reform platform, Volodymyr Zelensky was elected president of Ukraine in 2019 with more than 70 percent of the vote. In 2021 Putin ordered a buildup of troops along Russia’s border with Ukraine, and in February 2022, after he announced the beginning of a “special military operation,” Russian forces invaded Ukraine.