- Russia has good reason for focusing its military efforts on eastern Ukraine as the area is a major strategic, political and economic goal for the Kremlin.
- The Donbas region has nationalist importance for Moscow.
- Eastern Ukraine has been the location of conflict between pro-Russian separatists and Ukrainian fighters for eight years.
The "battle for Donbas" looks to be underway in Ukraine, as Russia concentrates its war machine on the eastern region — a major strategic, political and economic target for the Kremlin.
Having mostly pulled back from northern parts of Ukraine, Russia's long-anticipated offensive in the east appeared to begin in earnest on Monday, with its military forces unleashing attacks on a number of areas within the Donbas.
"It can now be stated that Russian troops have begun the battle for Donbas, for which they have been preparing for a long time," Ukrainian President Volodymyr Zelenskyy said Monday, adding that "a very large part of the entire Russian army is now focused on this offensive."
CNBC takes a look at the three main reasons why Russia is now focusing on eastern Ukraine:
A longtime focus for Russia, the Donbas region includes two Russian-backed separatist "republics" in Luhansk and Donetsk. They have been fighting Ukrainian forces for years.
Now, Russia's apparent refocus on the area comes after few military successes in the rest of Ukraine despite almost two months of fighting.
"[Russian President Vladimir] Putin has given up on his more ambitious goals completely," former U.S. Ambassador to Russia Michael McFaul commented Tuesday on Twitter, saying it was "very striking how they have changed the name of their war to 'special military operation in defense of Donbas.'"
Russia's forces appear to have been underprepared and ill-equipped to deal with the harsh fighting conditions in Ukraine and the strong resistance mounted by the country. Despite causing much destruction, Moscow has achieved relatively little — and it has failed to bring about the swift fall of the capital Kyiv and removal of Zelenskyy's pro-Western government.
As such, analysts believe this has prompted Russia to refocus its efforts on the complete takeovers of key strategic cities in southern Ukraine and on the Black Sea, for example the port cities of Mykolaiv, Mariupol and Kherson. The latter two are almost completely in Russian control, despite pockets of fierce resistance from Ukrainian fighters.
Russia is also thought to be looking to take over Odesa further up the coast to the west, although that's seen as a much harder task.
The Kremlin is seen to be striving to declare some kind of victory in Ukraine by May 9 — a day known as "Victory Day" that holds great national importance for Russia as it marks the Soviet Union's defeat in 1945 of Nazi Germany in World War II.
The Kyiv Independent newspaper reported in March that Russian troops were being told that the war must end by May 9, citing intelligence from the general staff of the armed forces of Ukraine. The Russian Defense Ministry was unavailable to immediately comment on this when contacted by CNBC.
Ukraine's Zelenskyy noted on Monday that an increasing number of attacks were recorded in the Donbas, near the cities of Izyum in the Kharkiv district and Sloviansk in the Donetsk district, as well as around Severodonetsk and Popasna in the Luhansk region, further east.
Separately, a senior U.S. Defense official confirmed on Monday that Russian forces have added to their footprint inside of Ukraine, with nearly all of their ground forces deployed to eastern and southern parts of the country.
A "win" in eastern Ukraine is not only key for Russia in terms of its military strategy; it has significant economic value, too.
Firstly, the Donbas itself is a heavily industrialized region known for its coal mining industry and large coal reserves that Russia could potentially access if it annexed the entire region.
And secondly, control of the region would also enable Russia to create a "land bridge" to Crimea, which it annexed from Ukraine in 2014, and which is a vital military and trading hub for Moscow on the Black Sea.
This push to be able to access Crimea by land is a key reason that the southern port city of Mariupol — which is directly in the path of a possible land bridge — has been the focus for Russian attacks and Ukrainian resistance: winning or losing it has big consequences for both sides.
Eurasia Group founder and President Ian Bremmer noted that Russia was now in "phase two" of its invasion, with different strategic objectives.
This includes "capturing all of the Donbas" including the Donetsk and Luhansk provinces, he said in emailed comments Monday, and securing a land bridge from the region to Crimea.
He said Russia's other goals included to fully control the city of Kherson — crucial to securing the freshwater canals to Crimea that the Ukrainians have cut off — and to seize "some buffer territory to hold it all comfortably."
The Donbas region is also important to Russia when it comes to its own national identity and its influence over former Soviet territories — and the people within them that still identify as being Russian.
Indeed, Russia's self-proclaimed "defense" of ethnic Russians in the Luhansk and Donetsk regions (which are overwhelmingly Russian-speaking) has formed a large part of its justification for invading Ukraine.
The area is no stranger to conflict; the self-proclaimed Donetsk and Luhansk People's Republics have been the location of fighting between Russian-backed separatists and Ukrainian forces ever since Russia annexed Crimea from Ukraine. Figures vary, but it's believed that around 14,000 people were killed during the prolonged but lower-level conflict in the area.
Aside from the conflict, over the last eight years analysts say Russia has been sowing the seeds that would enable it to annex the Luhansk and Donetsk regions with attempts to "Russify" the areas, such as offering Russian passports and citizenship to residents there since 2019.
Political analysts saw this as a cynical precursor to an incursion, because Russia could defend such a move by saying it was seeking to "protect" its citizens from Ukraine. Russian state media has focused on Donbas residents fleeing in recent weeks, repeatedly accusing Ukraine's military of war crimes in the region, allegations denied by Ukraine.
For its part, Russia has repeatedly denied backing rebels in the Luhansk and Donetsk areas, despite evidence of financial support for the breakaway "republics" and Russian weapons being used by separatists to fight Ukrainian forces.