What three major events besides WW2 have most shaped the evolution of the European Union?

I have chose 3 events such as the Cold War and creation of NATO, the four treaties that make up the institutions: TEU, Amsterdam, Nice, Constitutional treaty, and the French empty chair crisis along with the Luxembourg compromise. Are there any other major events that helped shaped the evolution of the EU? If so, let me know because I am not sure if I should use the one's that I already have.