The Russian invasion of Ukraine began Feb. 24th, 2022, with three a pronged attack. One of the prongs came from the Crimea that Russia had stolen in 2014 from Ukraine. Now, Putin wanted all of the Ukraine and acted just like the Nazis did in WW2 with scorched earth policies as they went from Russian town to town, razing everything and slaughtering many.
One key strategic attack was to create the land bridge from the Crimea to the Donbas region. So, when the Russian broke out of their box in Crimea one force went right towards Mariupol and Donbas, while the other went left, hoping to take Odessa. Forces attacking from the Donbas region also were directed at Mariupol.
Mariupol was a thriving urban port of 500,000 or so and would become the scene of the most violent and horrific fighting of the Ukraine war. It was an industrial city with its Azovstal Steel works factory that was a maze on top of the ground and far beneath with its tunnels. The city had several residential areas and was a beautiful Ukrainian city.
Upon the arrival of the Russian Army beginning in early March, the Ukrainian defenders fought a valiant defense that would enhance any NATO union had NATO accepted them. The Russians used the old tactic of divide and conquer the city by attacking various residential and urban areas in order to isolate the steel works factory. The artillery and air barrages literally obliterated these areas into hollowed zombie-like zones with few citizens, much like at Stalingrad. Whole areas were unlivable, and residents were either trapped or escaped. As time went on, the Russian forces had cutoff the city from everything except bombardment, the favorite Russian tactic since WW2. No place was safe, and it is estimated that around 20,000 residents were killed by this method of war. Food, water, electricity, all were in scarce supply, if available at all. As the Russian forces chopped off sections of the city one by one and "cleared them", the noose around the Ukrainian defenders shrunk smaller and smaller just like what the Germans did at Stalingrad with the Russian defenders! Putin surely uses the same ruthless tactics and it is the Russians who are the "Nazis" in this war.
By April, Mariupol was still not cleared. The heroic Ukrainian defenders, though dwindling in numbers, were far superb to those Russian conscripts who raped, killed, looted, from the Ukrainian homes and even bragged about it to their loved ones as radio intercepts reveal. How can Putin look the other way when he, himself, has two daughters?! Some women or girls were raped many times in cellars and then shot in the head. The Russian Army is barbaric and nothing has changed since they stormed Berlin in 1945, where they did same exact thing!
By mid-April, some 40+ days after Mariupol had been under siege, not much was left of the once cosmopolitan city. It was all in complete, utter ruin, and unhabitual. By now, the several Russian battalion groups of 600+ men and Chechens (which fought a bitter battle against Russia in the 1990s at Grozny) had closed the noose around the Azovstal Steel plant fairly tight leaving around 2000 Ukrainian soldiers from the Azov and 36th Regiments. Those Ukrainian units that had ran out of food and ammunition did surrender but most did not and vowed to fight to the end even when Russia offered them "safe passage" if they would surrender. Those Ukrainians were making their last stand at the steel plant factory!
Mariupol was critical to control as the main roads and rail lines went through it in several places, in addition to it being an important port complex. Even though the Russians were able to clear much of the city, some of the roads and rail went through the steel works area. While it was not vital to control it, the siege became more and more a symbol to both sides just like Stalingrad. For Russia, it was tying down needed forces that could be used elsewhere as the attack stalled. For the Ukrainians, it became a "battle cry" to defy the Russian invader and rally Ukrainian forces who were so outnumbered in this David versus Goliath battle.
The Russians ultimately decided to simply contain the enemy forces hunkering down in the underground tunnels of the Azovstal industrial zone. They could afford to just starve them instead of risking more loss of life. Sooner than later, the heroic stand of the Ukrainian units would have to surrender as they ran out of food and ammo. Russian aircraft and artillery continued to bombard them to no avail and penetrate some of the underground bunkers or tunnels. The Russians still have not yet made a decision to use chlorine gas to force them out, which would be the case, unless they have gas masks. They could also use sarin gas, which would penetrate the masks and kill them.
The ending at Mariupol will be tragic and sad for the Ukrainians, but it will also go down in history as yet another great siege battle of the 21st Century!