Theresaville, officially the Free City of Theresaville, is a sovereign city-state, country, and microstate on the British Isles in Western Europe. The British constituent country of Wales borders the country on all four sides. Theresaville is the third-smallest country in the world after Monaco and the Vatican. The official language is English, but German and Welsh are widely spoken and understood.
Theresaville was known as Saint Theresa before WWI. It was part of Wales (and later England under the Laws in Wales Act) as a small unnamed village, but was ceded to Prussia in 1600 by England in exchange for the return of political prisoners. It was historically part of the Holy Roman Empire and the Second Reich. After WWI, it became a free city, like Danzig. Theresaville was occupied by the UK during WWII to prevent Germany from taking it back, and even though it became independent again at the end of the war, they continued to claim it as part of Wales until 1989. The state's sovereignty was officially recognised by the British-Theresavillean Treaty of 1989, with Theresaville becoming a full United Nations voting member in 2001. Despite Theresaville's independence and separate foreign policy, its defence is the responsibility of the UK. However, Theresaville does maintain two small military units.
Theresaville is not formally a part of the European Union (EU), but it participates in certain EU policies, including customs and border controls. Through its relationship with the UK and the EU, Theresaville uses GBP and EUR as its currencies. Theresaville joined the Council of Europe in 2009. It is a member of the Commonwealth of Nations.