As a response to Euromaidan and pro-Russian unrests in Eastern Ukraine, Russia deployed its troops in Donbass region to support Novorossiya's Resistance. This act was considered as an act of hostility by Ukraine, that immediately declared war to Russia, and with overwhelming power invaded Crimea and Eastern Ukraine. In september 2015, United States invited Ukraine to join NATO, which caused whole NATO coming to war with Russia. Russia, unable to resist the armies of both superpowers, fell within four months.