Two armed conflicts were active in Europe in 2021: the interstate border conflict between Armenia and Azerbaijan for control of Nagorno-Karabakh, and the ongoing, low-intensity, internationalized, subnational armed conflict in Ukraine. In late 2021 a second large-scale Russian military build-up near Ukraine’s borders raised fears of the conflict in Ukraine escalating into a major interstate armed conflict—this happened in February 2022.
Ukraine has been the focus of Europe’s main territorial conflict since the annexation of Crimea by Russia in March 2014 and the ensuing outbreak of armed conflict in eastern Ukraine in an area often referred to as Donbas. After simmering at a low level for months, the armed conflict in Donbas escalated again in March and April 2021 as Russian-backed rebels and Ukrainian Government forces clashed in violation of the July 2020 ceasefire agreement.
Tensions further increased as Russia deployed tens of thousands of additional troops along the border with Ukraine in late March–early April 2021. In November, with peace talks stalled, Russia once again deployed thousands of troops near its border with Ukraine, having only partially pulled back its forces from the April build-up. Although Russia’s motives and objectives appeared deliberately ambiguous, President Vladimir Putin seemed at that time to be using the threat of invasion to secure both a more acquiescent Ukraine and extensive changes to the European security order, as well as to project strength to the Russian populace.
The Ukraine conflict was the focal point for persistent tensions between Russia and the rest of Europe over several issues, including cyberattacks, the treatment of Russian opposition leader Alexei Navalny, the political crisis in Belarus, and the strengthening of bilateral security cooperation between China and Russia. In December 2021 these tensions culminated with Russia tabling security demands in two draft treaties that were due to be discussed in a series of early January 2022 meetings with the United States and the North Atlantic Treaty Organization (NATO). Russia stressed that failure to endorse the documents would lead to an unspecified but serious military response, although there was very little in the texts that was likely to be accepted by either the USA or NATO.
Elsewhere in Europe, tensions persisted in largely quiescent but unresolved conflicts in the post-Soviet space, the Western Balkans and Cyprus. The November 2020 ceasefire between Armenia and Azerbaijan largely held in areas where Russian peacekeepers were deployed, but in other areas battle-related deaths from sporadic clashes and ceasefire violations remained above the threshold for an armed conflict. There were also serious and complex security challenges in Europe’s southern neighbourhood and beyond, especially in the eastern Mediterranean.
There were 19 multilateral peace operations active in Europe in 2021, one more than in the previous year.