You can form the European Union in 1812. Because it's good in theory!
However. Just like with the real EU, it is prone to crashing after meeting with another faction in a foreign country, and you will have to meet again in the same place to talk about the same things again another two maybe three times.

You can form the European Union in 1812. Because it's good in theory! However. Just like with the real EU, it is prone to crashing after meeting with another faction in a foreign country, and you will have to meet again in the same place to talk about the same things again another two maybe three times.