The UKCS is far enough away from Minnesota that most inhabitants aren’t aware of its existence. Those who are largely know it as the nation with the largest and furthest reaching merchant fleet this side of the Atlantic.
The origins are shrouded in distance and folklore, but by the 23rd Century, the UKCS was in control of the vast majority of the Caribbean islands, and several cities and communities in Florida, the Yucatan, Panama and the northern coast of South America. The UKCS was responsible for re-opening the Panama Canal and re-establishing permanent and serious trade with Europe.
The UKCS was marked by an intricate royal family. The de Windt family, from Saint Martin, is connected to each constituent state by marriage, either to the noble family (in autocratic states) or a powerful commercial or political family (in democratic states). This was meant to establish a blood bond between every state. Its success is debatable. Governing was done by a Federal government, with a lower house of elected officials and an upper house of landed nobles.
The UKCS was an early opponent of the Commonwealth, whose merchant marine was a direct competitor to their own. Building up their navy in anticipate of war, the UKCS fought valiantly but was ultimately unsuccessful, losing a significant number of ships and personnel to the Commonwealth fleet. Surrendering late in 2456, the UKCS survived to become part of the Commonwealth, albeit without the Federal Government. In some ways, the UKCS thrives under the Commonwealth, with vast tracts of southeastern Atlantic America ceded to the kingdom for cultivation.