The European migrant crisis or European refugee crisis began as early as mid-2014, when a rising number of refugees and migrants, from mainly Arab and African countries, made the journey to Europe across the mediterranean or by land to seek asylum in western european nations. This crisis has caused the rise of all kinds of extremism in Europe, with Jihadism promoting terror attacks in European clay, and provoking a right-wing populist response.
The European Migrant Crisis is a world event, starting in 2014 which involves migrants from many Middle Eastern and Central, East and Northern Africa.
Due to the recent conflict caused by ISISball, among other assorted problems in the regions,
as well as Merkel inviting them all in, migrants from the aforementioned areas began pouring into Europe - at the crisis' peak in late 2015, over a million migrants moved into the EU or bordering EU countries either though the Balkans, or by crossing the Mediterranean by boat from the destroyed Libyaball.
The main problem with the migrants entering Europe is that there are many Afghans, Iraqis, and Sub-Saharan Africans among them, which are economic migrants and not actual refugees fleeing from war in Iraq or Syria, making them fake their identity to enter illegally. Not helping the matter are the lack of border control in the Schengen area (EU's free movement zone) and the fact that Europeans seemingly can't tell Middle Eastballs apart, understandably annoying Syriaballs.
As for the migrants crossing into Europe through the Mediterranean, there have been accusations that people smugglers are purposefully sending migrants into the sea at a price, knowing that NGO ships will rescue them and take them to European ports.
Different countryballs have dealt with these migrants in different ways. Germanyball and Swedenball openly welcomed these migrants to enter and settle. It has now got to a point that there are too many migrants to house and feed in those 2 countries, and a suspicious rise in crime as well (when they finally get theirs...). Western European nations were more accepting of the migrants, while the V4 nations (as can be seen in a comic below) were much more hostile due to there only being homogeneous Catholicballs within their clay. Notably, Hungaryball quickly built a barbed fence to keep the migrant horde away.
Much to the internet's surprise, Serbiaball hasn't been ultra hostile, probably since "Remove Kebab" only really ever applied to Euro/Wahhabi Muslimballs within context, and he just prefers to shove the migrants upward in Europe. It helps that the migrants aren't preferring to seek refuge in Serbia anyway and that he's been a fan of Arab nationalist leaders and their followers since the 90s.
Community support has lowered for the acceptance of these migrants. This is leading to the rise of far right wing political parties in Western Europe, such as in Austriaball and more recently Italyball. These far right parties have been campaigning on on the sentiment that the migrantballs and lack of border controls threaten security and will change their ways of life and bring sharia law to the continent, although only Salafi and Wahhabi balls really want that. Even then, there is the issue of finding out which Muslimball is a Salafi/Wahhabi (so in some comics, expect ISISball to be wearing a secular Syria flag for instance).
The most recent solution involves these migrants being sent to Turkeyball, which ultimately means deportation in most cases. Turkeyball accepted the deal because they want to be into EUball, but some syriaballs are hesitant since Turkey is one of the balls escalating the conflict. The Gulf Countryballs are also getting lots of hate right now due to being sponsors of the conflict and doing squat to let the migrants in, preferring Europe do the hard work and only sending paltry money (hence why you never really see Gulf Countryballs in comics about migrants). Similar criticism has been applied to USAball and Russiaball at times, but this isn't referenced that much in comics.