Every 9 May, Europeans celebrate Europe Day, a commemorative occasion that honours the starting point of the continent's political and economic integration, and the peace achieved as a result of the decades-long collective effort.
The celebration traces back to 1950, when Robert Schuman, then-French minister of foreign affairs, delivered his landmark declaration proposing that France and Germany -- two nations with a long and bloody history -- join their coal and steel production.
With this in mind, Schuman intended to accelerate the modernisation of both countries after the economic devastation and human carnage of World War II and to avoid a potential race of unfair competition.
By turning such critical industries so inextricably intertwined, the French minister had a higher goal: to make a new war materially unworkable.
"The solidarity in production thus established will make it plain that any war between France and Germany becomes not merely unthinkable, but materially impossible," Schuman said, while reading his declaration in the Salon de l'Horloge at the Quai d'Orsay in Paris on 9 May 1950.
Notably, Schuman left the door opened for other countries to come on board and achieve a genuinely united Europe -- an ambition pursued during the inter-war period that collapsed under the weight of national interests.
Schuman's pitch proved successful. West German Chancellor Konrad Adenauer said yes almost instantaneously.
Idea of united Europe progresses into European Union
A year later, on 18 April 1951, representatives from France, Germany, Italy, Belgium, the Netherlands and Luxembourg signed the Treaty of Paris and established the European Coal and Steel Community (ECSC), a pioneering organisation based on the principle of supranationalism.
Under the ECSC, nation-states began to pool their jealously guarded sovereign competences and transfer them to a series of European institutions: an independent High Authority, a Common Assembly of national parliamentarians, a Special Council of national ministers and a Court of Justice.
Schuman's close aide, Jean Monnet, who is now considered the mastermind behind the landmark declaration, was named the first president of the High Authority.
The economic benefits of the ECSC, like the custom-free market for coal and steel, convinced member states to go further and bring more sectors and policy areas under the supranational mandate.
The ECSC progressively evolved, first into the European Economic Community and, later, the European Union.
The original four institutions eventually turned into the European Commission, the European Parliament, the EU Council and the European Court of Justice that we know today.
The steady evolution of the political project, the likes of which humankind had never seen, cemented the status of the Schuman Declaration as the true genesis of European integration.
"Europe will not be made all at once, or according to a single plan. It will be built through concrete achievements which first create a de facto solidarity," the French statesman said in his speech.
Meeting in Milan in 1985, heads of state and government decided to officially name 9 May Europe Day to celebrate peace and unity in the continent.
The occasion became one of the main symbols of the European Union, together with the twelve-starred flag, the slogan In varietate concordia -- "united in diversity" -- and the anthem, which is based on Beethoven's "Ode to Joy".
The 2004 treaty establishing a Constitution for Europe was meant to turn the symbols into official emblems but the provision was dropped after the ratification process failed.
Interestingly, only two countries, Luxembourg -- where Schuman was born in 1886 -- and Kosovo -- a non-EU state with long-held EU aspirations -- have established Europe Day as a national holiday. In Romania, it coincides with independence day, while Croatia and Lithuania have legally recognised the day but without making it a public holiday.
The other member states celebrate Europe Day in a commemorative manner, by hoisting flags and organising a variety of events. In Brussels, the EU institutions hold an open doors day, which was cancelled two years in a row because of the coronavirus pandemic. Employees of the EU institutions are given a day off work.
This year, Europe Day will see the closing ceremony of the Conference on the Future of Europe, a yearlong exercise that has brought together citizens and policymakers to reform the bloc's political structure.
Two celebrations of Europe and two victory days
Europe Day is not the only holiday celebrated on 9 May, and amidst the war in Ukraine, all of the holidays that fall on this date are set to take on a new significance.
"The Kremlin's invasion reminds us why we are celebrating Europe day. The day when our peaceful, prosperous and united Europe was born," said Ursula von der Leyen, president of the European Commission, in a statement ahead of the occasion. "Seventy-two years later, Europe is stronger and more united than ever."
Besides European integration, 9 May is celebrated in other parts of Europe for another reason: the Soviet Union's victory over Nazi Germany in 1945.
Victory Day is today observed as national holiday in countries like Russia, Belarus, Georgia, Armenia, Azerbaijan, as well as Israel. In Moldova, the pro-EU faction tends to celebrate Europe Day instead.
In the rest of Europe, Victory in Europe Day is celebrated one day before, on 8 May.
The reason why the two parts of the continent celebrate the same holiday on two different dates, however, lies in the fact that Nazi Germany signed its second and last formal surrender late on 8 May 1945, when it was already 9 May in Moscow.
And on top of that, the EU's Europe Day is not the only Europe Day.
The Council of Europe, an international organisation with limited power whose mandate focuses on upholding human rights and democracy, celebrates its own Europe Day four days earlier on 5 May to mark the council's foundation.
The entity encompasses all European nations with the exception of Belarus, Russia, Vatican City and Kosovo.