Ask Lemmygrad

Prior to 2014, Ukraine has usually had Russian-friendly governments. Some more than others, but relations between the two countries were generally close, if sometimes strained.

In 2014 there was a coup in the Ukraine (or a revolution, or a series of protests that resulted in the president stepping down, whatever) called Euromaidan. These protests involved Neo-Nazi paramilitary groups (which are very common in Ukraine) marching in the streets. The government that emerged afterwards was solidly anti-Russian.

Separatists in the Donbass region (Eastern Ukraine, the parts that Russia is now occupying, which is about 50% Russian) immediately began trying to secede. Elections stopped being held in these regions, solidifying the anti-Russian government. Crimea, which is almost 100% Russian, was retaken by Russia with almost no resistance.

The Ukrainian War started in 2014 when the post-Euromaidan Ukrainian government began using artillery, snipers, and fascist paramilitary volunteers against the Donbass separatists. 2022 was just when the Russians decided to get involved.

The Russian government claims that the invasion was in order to "De-Nazify" Ukraine. The motivation to protect the Russian ethnic minority was also clear, but since Russia is a multi-ethnic federation, saying this sort of thing is a political no-no in Russia.

In reality, Russia invaded because Ukraine was considering membership in NATO. In 2008, Georgia was similarly considering membership in NATO. Russia then invaded and liberated the provinces of Abkhazia and South Ossetia, which remain independent to this day, and stationed troops in these regions permanently. This was done because, if they allowed Georgia into NATO, it would require NATO to defend Georgia; since NATO membership requires approval of all existing members, there is always going to be at least one member who is not eager for immediate war with Russia. This is the same thing that is happening in Ukraine: Russia is permanently occupying parts of Ukraine so that, if Ukraine were to join NATO, NATO would be obligated to "defend" them against Russia.