Here's some surface level things about the lore surrounding it.

1. Scramble for America: the invasion, conquest, and colonization of most of North America by the Dutch, English, German, Russian, Swedish, French, Spanish, Scottish, and Danish colonies from the 15th century to the 18th century, culminating into a war between the colonies following their spreading of their territory and eventual overlapping (which forms disputed zones) that lasts for a couple of years, ending with a formation of an organization whose mission is maintaining international peace and security, to develop friendly relations among colonial empires.
2. This does last a long time, but not long enough as a political movement led by displeased people formed overtime, then evolved into a successful revolution resulting in the formation of a sovereign country named America (Officially the United States of America) which takes the building reserved for the federation and makes it their government building and makes the town its in their capital.
3. After WWII: The Axis states were subject to military occupation for 80 years from 1945 (full military deoccupation is scheduled to be finished by 2025 as it calls for the dissolving dissolving being slow with small portions of land (maximum of 174600 feet; and one portion per week) being given back to these formerly Axial countries overtime) by the Allies of World War II with leases in key locations of the countries making up the former grouping by the latter grouping of countries.

Here's my take on MBA.