In 2014,
Russia made several incursions into
Ukrainian territory. Beginning with
Crimea,
Russian soldiers without insignias took control of strategic positions and infrastructure within the Ukrainian territory of Crimea, which Russia
annexed after a disputed
referendum. Subsequently, demonstrations by pro-Russian groups in the
Donbass area of Ukraine escalated into an
armed conflict between the Ukrainian government and separatist forces of the self-declared
Donetsk and
Lugansk People's Republics. In August, Russian military vehicles crossed the border in several locations of Donetsk Oblast The incursion by the Russian military was seen as responsible for the defeat of Ukrainian forces in early September.