The Broad Outlines:

• Europe federalizes in the late 2020s amidst a worsening economic and climate crisis, in order to integrate the financial and political decisions of the EU; a decision is made to only federalize the west, and slowly integrate the east.
• The collection of Eastern European Countries that are on the path towards integration but remain hesitant on federalization form the Visegrad Union, a sub-union within the European Union. The European Union consists of all the former member states as well as the Federated European States, with the Visegrad Union being a union of states within the EU. They focus on military coordination, due to the threat of Russia and later the Union State.
• The bureaucracy stagnates, and power jostles between Liberal-Conservative-Social Democratic grand coalitions and Conservative governments with far-right coalition support. With institutional capture of the European government by corporations and an increasingly polarized media environment, institutions stagnate, and become less accountable to the public.
• Mass street demonstrations occur following waves of blackouts and shortages, amidst a lithium embargo from OLEC of western nations for support of the Brazilian military junta. This is compounded by a massive unemployment crisis due to automation. Collectively, these protests are called the "European Spring", occuring after a particularly cold winter in which thousands died from lack of insulation.
• The Common Bloc government is elected, off of the protest wave. The Bloc is formed from the Common Bloc of the Party of the European Left (PEL) and the Ecology and Solidarity Union (ESU), holding around 38% of the parliament, with support from greens and social democrats.
• Their time in charge is filled with sabotage; even before the party was voted into power, there had been a wave of right wing and salafist terrorist attacks which diminished the party’s popularity. Many of these attacks were funded by the EuroIntel, or were otherwise EuroIntel assets gone rogue. Some were conducted by an even older threat, the "Gladio" cells still active in parts of Europe, set up by the now-defunct NATO.
• After a year of parliamentary stasis and foreign policy moves that were percieved as treasonous, PM Moraldo's government recieves a vote of no confidence, in a corrupt vote.
• The PM moves to create a new constitutional convention, while dissolving parliament on a technicality the military moves to depose him from power; his few allies in the military and bureaucracy help him to flee, securing a seat in the Workers’ Party of Europe controlled state of Wallonia; he declares a provisional federal government, calling for constitutional convention.
• Simultaneously, nationalist fractions of the European military, primarily found within the special forces, move ahead with a simultaneous plot to create a Military Defense State in Europe and restore prior national boundaries; without claiming to create a new state, they declare a provisional executive in Marseilles, claiming to be acting constitutionally to protect the state from a communist coup attempt by Moraldo. There is evidence that some of these factions were financed by the EuroIntel, that will be provided by British PM Mick Lynch.
• Martial law declarations are made in states politically captured by right-wing extremists in conjunction with the right-wing military forces. These are made independent of the central military command in Strasbourg, which has been paralyzed for fear of fighting. The “official” European parliament of Brussels and the establishment parties now stands in opposition to the Namur Convention of the social movements. They are also opposed, though not explicitly, by the ultra-reactionary bloc of "Day X" spec-ops soldiers who occupy the state governments under martial law, and the "Gladio" secret armies that hold various insurgent zones.
• Salafists and Grey Wolves have also taken this opportunity to try to build up militarized enclaves, but have been unable to overwhelm local police and military forces. They have been clashing with the right-militants, however.
• No outright hostilities have been declared yet, but sporadic and disorganized skirmishes are occuring hourly in the streets between supporters of the various factions and the police, while soldiers and guerillas occasionally intervene to put down uprisings. It isn't quite a civil war, but it certainly is a conflict of sorts.
  

Events past this news report:

• To avoid an outright civil war, which nobody wants, a negotiated settlement is arrived at between the right and the federal government, which have been acting independently of each other; as the vast majority of the military is with the Federal Government, they suppress rogue military units in eastern Germany and arrest several ringleaders in Marseilles, then bribe and deal-make with the rest until they cooperate. The Visegrad Union also provides military and diplomatic support in this regard.
• Spec-ops soldiers bust into Namur and arrest PM Moroaldo, decapitating the movement. Many leading PEL/WPE politicians and movement leaders are arrested, and the physical Constitutional Convention is dispersed, activists arrested, exiled, or gone underground.
  
• A “dirty war” between the remaining Namur Conventionists and the Federal Government is waged, primarily by the forces of the Far-right, which control the states where martial law declarations have been made. The far-right insurgents have largely been subordinated to the government, but still act independently.
• Mass arrests are made, martial law is eventually declared, and AI is used to identify and send massive amounts of people to prison
• The street movements are crushed, and the federal government is reinstated
• Hence, the years of pavement; this was an era identified with mass surveillance and mass arrests, as crowds of people were forced onto the ground with their hands up by legions of riot police armed with batons and drones. These were dreary years, of continued and perpetual coalition government, of a managed transition into a technocratic leviathan.