There are a few mistakes that need to be addressed here that might help clear things up for you.
First, Yugoslavia didn’t exist during the First World War: Serbia was independent and allied with Britain/France/America but other ex-YU countries were still part of either Austro-Hungary or the Ottoman Empire. Those parts were therefore not allies of “the west”, while Russia was.
Second, Yugoslavia was torn asunder during WWII, creating a complex civil war between Yugoslav fascists, nationalists, and communists. Tito’s communist Partizans were indeed part of the allies, just as the Soviets were. But significant portions of Yugoslavia were not, such as Serbian Chetniks (hyper nationalists who were borderline fascist) or Croatian Ustaše. In fact, the Ustaše controlled an independent fascist state comprised of modern day Croatia and BiH, and committed some of the worst atrocities seen during the war against its Serb minority (Jasenovac being the most notorious site/example).
Point here being: looking at the status of Yugoslavia (or the territories that once made it up) during either world war doesn’t really help answer your question because a) the territories that made up Yugoslavia were on both sides in both wars; and b) Russia/the USSR was on the allies side in both cases.
Now, Tito’s Yugoslavia (1945-1990) was in fact a western ally during the Cold War, but in a very complicated way. His brand of a “third way” was the foundation of the non-alignment movement that created a significant Cold War faction that refused to directly ally with either the US or Russia (Yugoslavia, India, Egypt, etc were part of this). So technically speaking, Yugoslavia was not a western ally in that sense. In reality, however, Tito rubbed shoulders with both the US and the USSR throughout the Cold War, playing both sides and receiving direct financial assistance from both blocs, depending on the time and circumstance we’re talking about. In sum: it’s a very muddy picture where Yugoslavia fit within the Cold War binary of “East vs West”.
Finally, the 1990s war is arguably the most important thing to consider here. When Slovenia and Croatia proclaimed independence, they actively catered their image to the West in order to gain support. This was a convenient way to gain support against Serbia as this was happening amongst the broader collapse of communism throughout all of Europe. Croatia, for instance, insisted it wasn’t “Balkan” but rather Central European, and pumped out a lot of wartime propaganda insisting on its “western” roots. They also unleashed a massive propaganda campaign that depicted the Serbs (technically still the communist Yugoslavs) as barbaric fascists, more “East” than “West”. Serbia, meanwhile, embraced a brand of nationalism that still insisted on its European roots but also focused on Serbian Orthodoxy (I.e the Serbian Orthodox Church) which many western observers automatically associate with “the East”. Thus, the wartime cultural politics/propaganda of each state fed into the simplified “East vs West” binary, intentionally or not.
That probably doesn’t fully answer your question but hopefully it helps clarify some things! Sources to consider:
John Lampe, Yugoslavia as History: Twice There Was A Country
John Allcock, Explaining Yugoslavia
Sabrina Ramet, Balkan Babel: the Disintegration of Yugoslavia from the Death of Tito to the Fall of Milosević
Vjekoslav Perica, Balkan Idols: Religion and Nationalism in Yugoslav States
Patrick Patterson, Bought and Sold: Living and Losinf the Good Life in Socialist Yugoslavia
Hi there! You’ve asked a question along the lines of ‘why didn’t I learn about X’. We’re happy to let this question stand, but there are a variety of reasons why you may find it hard to get a good answer to this question on /r/AskHistorians.
Firstly, school curricula and how they are taught vary strongly between different countries and even even different states. Additionally, how they are taught is often influenced by teachers having to compromise on how much time they can spend on any given topic. More information on your location and level of education might be helpful to answer this question.
Secondly, we have noticed that these questions are often phrased to be about people's individual experience but what they are really about is why a certain event is more prominent in popular narratives of history than others.
Instead of asking "Why haven't I learned about event ...", consider asking "What importance do scholars assign to event ... in the context of such and such history?" The latter question is often closer to what to what people actually want to know and is more likely to get a good answer from an expert. If you intend to ask the 'What importance do scholars assign to event X' question instead, let us know and we'll remove this question.
Thank you!