The war in Ukraine is more resembling the war between Croatia and the breakaway Republic of Serbian
Krajina.
Both wars were preceded by the political forces of the opposing side taking control of the country: in Croatia, Tuđman's Croatian Democratic Union won the elections, intending to secede from Yugoslavia; in Ukraine, the various political forces behind Euromaidan took control of Ukraine after overthrowing Yanukovich, intending to break ties with Russia and join the EU and NATO. Such goals were not particularly supported in Krajina and Donbass.
The opposing sides both in Croatia and Ukraine were perceived as the successors of old nationalist enemies: pro-secessionist Serbs in Krajina regarded the new Croatian government as the new Ustaše, pro-secessionist Russians and Ukrainians in Donbass regarded the new Ukrainian government as the new Banderites. Croatians and Ukrainians thought they were previously oppressed by their opponents and their home countries (Serbia, Russia).
Secessionist sentiments in Krajina and Donbass were boosted by the alleged threat to Serbian and Russian cultural identity posed by the new governments of Croatia and Ukraine - pro-secessionist Serbs thought the Croatian government would soon ban the usage of the Cyrillic script, pro-secessionist Russians were concerned about the alleged ban on using the Russian language.
Eventually, secessionist sentiments resulted in the proclamation of autonomous regions which soon declared independence - in Croatia, it was SAO Krajina, which eventually became Republic of Serbian Krajina, in Ukraine - the People's Republics of Donetsk and Lugansk, which united into Novorossiya later on. Both Serbian Krajina and Novorossiya originally intended to reunify with their home countries.
The armed forces of both Serbian Krajina and Novorossiya were originally armed militias. Both Serb and Novorossiyan forces were armed by their home countries.
Croatia was backed by the US and the EU, so is Ukraine right now.
Serbian Krajina was perceived by Croatia and the West to be a devious plot concocted by Serbian President Milosevic, whose main goal was alleged to be the conquest of Croatia in order to create Greater Serbia. Novorossiya is perceived by Ukraine and the West to be a devious plot concocted by Russian President Putin, whose main goal is alleged to be the conquest of Ukraine in order to
re-create the Soviet Union or something similar. As the result, the US and the EU enacted wide-reaching sanctions against both Serbia and Russia.
Both in Croatia and in Ukraine there was a internationally mediated ceasefire, which was soon broken and after which the frontlines froze and the war stalled.
Milosevic constantly tried to get rid of Serbian Krajina in order to amend his relations with the West, while the Serbian Krajina intended to continue fighting. Putin is currently trying to do exactly the same.
The economy of Serbian Krajina, devastated by the war, couldn't function without support from Serbia. Eventually the leadership of Serbian Krajina became more and more divided and increasingly corrupt. The same thing is currently going on in Novorossiya - its economy cannot function without Russian aid, and its leadership is also becoming increasingly divided, according to numerous reports by Colonel Cassad. Furthermore, the Novorossiyan leadership were caught selling coal to their enemy, Ukraine.
Eventually, the Republic of Serbian Krajina was crushed by Croatian forces. Milosevic's attempts to normalize relations with America and the EU failed, and his conflict with the West resulted in a disaster
for both Serbia and
Milosevic himself. It's unclear whether such a fate is destined for Russia and Putin or not. Igor Strelkov warned Putin numerous times in his public addresses that his non-interventionist policies would lead Russia into certain doom. Putin ignored him.
The main differences between the wars in Croatia and Ukraine are:
1. The ethnic differences between the opposing sides in Ukraine are very blurry - political factors are the main dividing factors there.
2.
Thankfully, there was no ethnic cleansing in Donbass, unlike in Croatia.3. Different original goals of Ukraine and Croatia - Croatia aimed to secede from Yugoslavia, Ukraine, which is already an independent state, is trying to break all ties with Russia and join the EU and NATO.
3. The participation of the JNA and the Russian Army is very different - the Yugoslav People's Army, which supported the Croatian Serbs, openly fought Croatia at the beginning of the war, its aim being the preservation of the territorial integrity of Yugoslavia. Hostilities between them ceased in 1992, after that date, Serbia never sent its troops to Croatia and only supplied Serbian Krajina with arms, ammunition and other supplies.
The Russian Army never intervened openly in the conflict, its intervention near Mariupol in August 2014 was a covert operation aimed at preventing the collapse of DNR and LNR. It is also supplying DNR and LNR with arms.