You're right in that the Ukraine isn't, nor has it ever been, a region with a simple history. The Ukraine means 'borderland', and since deep into prehistory it has been the back door into Europe that has incessantly driven invasion, conquest, trade, and innovation as well. From the W. Asian steppes came pastoral agriculture, the wheeled cart and chariot, dairy, and always war, since the glaciers that prevented Europe from being habitable at all receded.
"...the first time Russia had invaded Ukraine in recent history."
Lenin created the Ukraine in the 1920s, and up to it's dissolution, the Soviets added bits and pieces to it from the neighboring states then part of the USSR. From the birth of the Rus in Kiev under Varangian and Viking traders, to the domination of Asia to the very gates of Europe by the Mongols, over and over again the Ukraine has been the mangled borders of contested imperial power, ethnic, and economic conquest. Today is nothing new.
"...a simple explanation of how Ukraine ended up at war with Russia."
The historical record is written, and easily available to anyone that seeks it. The gateway to Europe has ever been the prize of warlords, empires, and profiteers, and this has never changed, though the USSR had pressed it's imperial boundary well beyond it into the heart of Europe, and tried to turn the Ukraine into the heartland of that empire, rather than it's boundary.
IMG source - deep in the Stygian depths of darkness known as /pol/
As corruption and profiteering fulfilled Dmowski's prophecy for decades, the collapse of the USSR cast the Ukraine loose of it's bonds to empire, and then the adventurous and least ethically constrained of criminals hell bent on profiting from corruption have pitted it's many ethnic groups, Greeks, and Bulgarians, Jews and Turks, Russians and Romanians, Hungarians, and Poles, Tatars and Cossacks, one against the others, and in the early 2010s a unique blend of Jews and Nazis was wielded by Ihor Kholomoisky as gangs of armed thugs to take over factories and commercial businesses in the Ukraine. Azov, Right Sector, and the neonazi street thugs became mercenaries - and the perfect vehicles for more advanced corruption by CIA and Mossad, to enable the Ukraine to be conquered just as the commercial enterprises had been.
IMG source - some anonymous reporter of facts that somehow avoided decapitation
From there the record of biowarfare labs, NED/CIA trained agents provocateur, and the Maidan overthrowing the fragile democratic government - just as Dmowski had predicted - is pretty well known. When in 2014 the Fascists, now CIA trained revolutionary forces began burning Russian speaking people alive, sniping police and protestors alike, and shelling the Russian speaking peoples of the Donbas, Russia moved to secure it's Black Sea fleet in Crimea, and when Ukrainian troops massed on the border of the Donbas to ethnically cleanse it of Russian speaking peoples, most of whom had extended families in Russia, the Russian military quickly acted to prevent that genocide, driving elite military forces to the edge of Kiev and prompting Zelensky to surrender.
After all, he had been elected on a peace platform, and only after being threatened by the well armed Fascist gangs had he undertaken war - and the endless flows of money from the West. That is when Russia pulled back to enable political reorganization of the Ukraine to be undertaken, when BoJo visited Zelensky and the Ukraine betrayed their agreement with Russia, using the Russian retreat to get it's forces in position to start the protracted conflict that has ensued.
"...the US negotiating peace with Putin, without having Zelensky being part of said conversation."
Zelensky never was more than a puppet to the imperial forces doing battle over the corrupt profits to be made in the Ukraine. After he was elected by the people of the Ukraine to move towards the EU, peace, and they hoped, prosperity, the outrageous profiteering forces quickly subsumed democracy with military force. Zelensky was never more than a mouthpiece for Kholomoisky, who funded his campaign, and has only played his part as a plucky President of a war-ravaged country pleading for resources plundered and kicked back, sold on the dark web to Mexican cartels. There is no role such a patsy of profiteers has at the table when the actual warlords are talking.
That's about as simply and briefly as I can put it.
Thanks!
"deep in the Stygian depths of darkness known as /pol/"
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I wasn't sure anyone was checking to make sure I attributed pics properly. I'm now sure folks are, and glad it is my religious practice to do so.
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I'm going to dedicate a good hour towards learning and verifying this information. Thank you for sharing it.
I am sorry to have to open that gateway to you, as it isn't pretty no matter what side you try to look at it from.