1920
Originally not much more than a disorganized group of wanderers moving from commune to commune, who happened to share lineage, culture, and technology, the geographically isolated Aethelians decided to start forming cities. This is partly due to the invention of the personal camera, which allowed people to enjoy the beautiful land through pictures, rather than be forced to see it all in person. It was also partly because everyone's feet hurt from walking cross-country.
The Six Cities formed, all with different cultural highlights, but it wasn't enough, the people wanted to experience it all at once, so they chose the center point of The Six Cities as a good spot to build a capital, bringing in ideas from all of Aethelia to make it the cultural beacon of the nation (and later, the world, after they discovered how many other nations there are).
As worldwide travel became more common, Aethelians started to realize how common nations were across the world, and they decided to form one too. Being very diverse, and divided, though not hostile to each other, it was difficult to get everyone together. The nation's first leader decided to unite everyone with a huge party in the capital, the only way to guarantee where an Aethelian will be at any given time, where everyone with influence was invited.
Among the fun, everyone agreed to form one government, but differed on how to do things. Breaking off to form their own parties, the founder of the New Democratic Party formed from those who thought the original party wasn't inclusive enough, the Path To The Future Party thought there wasn't enough tech at the party, the Aethelia First Party formed from those who thought the party was so good, that The Six Cities were inferior in comparison, the Ultor Corporation formed from those thought the party needed to be more profit-driven, and in the corner, Adam the First watched silently, in hopes that someday, the name Adam would one day control it all, while the Selene Cultists were busy trying to 'bless' the punch bowl.
With the common goal of making Aethelia the #1 place to be, the parties turned into political parties, which formed the Aethelian parliament in 1947, as the people of The Six Cities and the capital voted for representatives for a central government for the first time.