As a European, I doubt that unless you are thinking balkan scale wars on the edges of Europe in countries that are not normally considered Europe as the term in commonly used or possibly Turkey actually get of its ass and do something about ISIS.
It is true that there are a lot of rivalries, but nobody wants another world war. We are all fat, rich (relatively compared to 1939) and entertained, but more importantly there would be nothing to win and a lot to lose. The same goes for civil war - Scotland isn't going to war, nor is Catalonia. Northern Ireland is more peaceful than it has been in decades and no country is seriously oppressing any other country.
Even Putin isn't stupid enough to go into a NATO country, at least not the way he did in Ukraine.
On what time-scale are you looking? A decade out? Two? Three? Europe is in flux in a way that it hasn't been in a long time. And I mean that in a downward way, until the mid 00's we were converging, since then we have been diverging with the '08 crisis as one catalyst and the whole nationalist resurgence as another. Add a couple of million refugees as a convenient scapegoat and the stage is set. Between Le Pen, Wilders and a bunch of other Euro-sceptic parties as well as a widespread fear of everything that isn't lily white you'd have to be a tremendous optimist to think that Western Europe has somehow become immune against war. I hope you're right but the signs are definitely not 'all good' and it would need some serious good news (such as the populists being voted out to the point of insignificance) before I'd be ready to believe it.
Mind you, I'm not pessimistic, I think we'd largely survive such an ordeal, it will never be on the scale of WWII (at least, that is something you'd hope) but it might take more than just a skirmish before the lessons of old would be re-learned. One of the reasons the anti-war sentiment in Europe was so strong in the 1970's and early 1980's is that we were under no illusion what would be the battle field, today the fact that we have the illusion that the battlefield would be anywhere but here is what endangers us more than anything. Two days driving separates the Russian border from Amsterdam, add another one and you've gone from Amsterdam to Bulgaria. Conflicts could easily spill over from one region to another. The first world war arguably started with a single shot, the second followed from that first. I have no idea what Europe would feel important enough to go to war over but it could just as easily be something insignificant as something big.
The most important thing (apologies to Spain, Italy, Romania and Poland) would seem to me to be that Germany, the UK and France keep seeing eye-to-eye. If those ever find themselves on opposite sides of some kind of confrontation all bets are off.
And it's not like the existence of the UN means much (2003 Iraq invasion) when a certain western superpower can bend, break and bulldozer members' arms to get their votes.:
"The Institute for Policy Studies published a report[10] analyzing what it called the "arm-twisting offensive" by the United States government to get nations to support it. Although President Bush described nations supporting him as the "coalition of the willing", the report concluded that it was more accurately described as a "coalition of the coerced." According to the report, most nations supporting Bush "were recruited through coercion, bullying, and bribery."" – https://en.wikipedia.org/wiki/United_Nations_Security_Counci...
The EU might seem fragile, but that is because the NATO and the EU expanded to fast. Remember some 20 years ago there was a wall through Berlin, now nearly everybody behind that wall has joined. Russia destabilized Ukraine to stop this movement.
Still the EU welcomed Croatia in 2013 and the Eurozone Estonia in 2011, so it is growing.
North-Western Europe already has a large coalition of countries that want and think the same things and have an excellent standard of living. The East will catch up economically and the South will get back on its feet. It will take some time, but I think they will join the group.
Some countries like the UK want their special treatment once in a while, but everybody knows, that London has to play along to some degree if it wants to stay the financial center of Europe.
Nobody wanted a world war in 1914 either. History is littered with the outcomes of unforeseen nonlinearities.
Northern Ireland is more peaceful than it has been in decades
It is now, but why do you assume that that is a one-way street? Northern Ireland was also relatively peaceful from 1922 to 1968, when Catholics became more aggressive about their demands for civil rights and violent conflict broke out and then escalated rapidly.
Across Europe as a whole (and also the US and other places), look at the rise of populist/ideological politicians. A few decades ago they would have been too marginal to succeed in many elections, but the internet has proved a great organizing tool even for people who want to reduce the scope of civil liberties, just as weapon technology doesn't discriminate based on the morality of who is deploying it against whom. Hardcore ideological politicians are unmoved by or even hostile to arguments about the greater good.
Nobody wanted a world war, but lots of people wanted a war between Germany and Russia, which would drag France into it. They just assumed it could be over quickly and they would be the victors (and it came very close to being true for the Germans. Had the Miracle on the Marn not happened or had Russia mobilized slower the Germans might really have out flanked the French army).
Hitler assumed he would be able to get away with taking Poland, as he had gotten away with taking pretty much anything up to that point and the Germans were extremely pissed over the Versey treaty, so much so that they were willing to go along with it.
Today we know what happens if we go to war with each other, and if anybody in Germany doubts it, they can go see the huge hill outside Berlin (or inside it) were they dumped all the broken bricks that couldn't be reused when the war ended and they had to rebuild the city.
So yeah, that is why I don't believe there will be another war in Europe proper again at least for the next 100 years.
It is true that there are a lot of rivalries, but nobody wants another world war. We are all fat, rich (relatively compared to 1939) and entertained, but more importantly there would be nothing to win and a lot to lose. The same goes for civil war - Scotland isn't going to war, nor is Catalonia. Northern Ireland is more peaceful than it has been in decades and no country is seriously oppressing any other country.
Even Putin isn't stupid enough to go into a NATO country, at least not the way he did in Ukraine.