The Republic of Mushroom Union is a massive, socially progressive nation, ruled by GoombaKoopa with a fair hand, and renowned for its prohibition of alcohol, smutty television, and anti-smoking policies. The compassionate, democratic population of 1.319 billion Shroomers love a good election, and the government gives them plenty of them. Universities tend to be full of students debating the merits of various civil and political rights, while businesses are tightly regulated and the wealthy viewed with suspicion.

The enormous, socially-minded, outspoken government juggles the competing demands of Administration, Education, and Environment. It meets to discuss matters of state in the capital city of Mushroom Port. The average income tax rate is 90.4%, and even higher for the wealthy.

The frighteningly efficient Shroom economy, worth 138 trillion Nelphs a year, is driven entirely by a combination of government and state-owned industry, with private enterprise illegal. The industrial sector, which is highly specialized, is led by the Information Technology industry, with major contributions from Tourism and Book Publishing. Average income is an impressive 105,297 Nelphs, and distributed extremely evenly, with practically no difference between the richest and poorest citizens.

The nation's Medal of Honour can be found as a free toy in breakfast cereal, solid-gold toilets are Shroom prisons' least expensive furnishings, companies struggle to cover for the hordes of employees on parental leave, and the people are famous throughout the region for their perfect yellow teeth. Crime, especially youth-related, is totally unknown, thanks to a capable police force and progressive social policies in education and welfare. Mushroom Union's national animal is the Goomba, which frolics freely in the nation's many lush forests, and its national religion is Christianity.

Mushroom Union is ranked 8,120^th in the world and 194^th in Europe for Most Beautiful Environments, with 1,867.1 pounds of wildlife per square mile.