The Holy Empire of Amestris-Britannia is a colossal, safe nation, ruled by Aoki vi Britannia - 宇宙の錬金術師 with an even hand, and remarkable for its infamous sell-swords, frequent executions, and punitive income tax rates. The hard-working, democratic population of 7.43 billion Amestris-Britannians have some civil rights, but not too many, enjoy the freedom to spend their money however they like, to a point, and take part in free and open elections, although not too often.

The enormous government juggles the competing demands of Education, Healthcare, and Environment. It meets to discuss matters of state in the capital city of Amestris. The average income tax rate is 76.0%, and even higher for the wealthy.

The all-consuming Amestris-Britannian economy, worth 502 trillion Sekkis a year, is highly specialized and led by the Information Technology industry, with significant contributions from Book Publishing, Basket Weaving, and Uranium Mining. State-owned companies are reasonably common. Average income is 67,612 Sekkis, and evenly distributed, with the richest citizens earning only 2.3 times as much as the poorest.

The government has declined to declare any particular religion as its 'official' one, families waiting for delayed pipe installations hope daily for rain, police officers often head to work wearing onesies and fluffy pink bunny-slippers, and snap elections are called over every minor impasse. Crime is totally unknown, thanks to a well-funded police force and progressive social policies in education and welfare. Amestris-Britannia's national animal is the Rat, which frolics freely in the nation's many lush forests, and its national religion is Freedom of worship.

Amestris-Britannia is ranked 123,703^rd in the world and 5,214^th in The North Pacific for Highest Wealthy Incomes, with 99,486 Standard Monetary Units.