Corpus separatum is a Latin term referring to a city or region which is given a special legal and political status different from its environment, but which falls short of being sovereign, or an independent city state. The term may refer to:
Corpus separatum (Latin for "separated body") is a term used to describe the Jerusalem area in the 1947 United Nations Partition Plan for Palestine. According to the plan the city would be placed under international regime, conferring it a special status due to its shared religious importance. The corpus separatum was one of the main issues of the Lausanne Conference of 1949, besides the other borders and the question of the right of return of Palestinian refugees. The plan was adopted by the General Assembly with a two-thirds majority, although its implementation failed and nowadays the view that Jerusalem should be the capital of both Israel and Palestine is widely supported internationally.
With its many holy places and its association with three world religions, Jerusalem had international importance. The United Nations wanted to preserve this status after termination of the British Mandate and guarantee its accessibility. Therefore, the General Assembly proposed a corpus separatum, as described in Resolution 181. It was to be "under a special international regime and shall be administered by the United Nations". The administering body would be the United Nations Trusteeship Council, one of the five UN "Charter" organs. (See Resolution 181, Part III (A).))
The Corpus separatum of Fiume (formally known as City of Fiume and its district (Hungarian: Fiume város és kerülete) was the name of the legal and political status of the city of Fiume (now modern Rijeka), instituted by Empress Maria Theresa in 1776, determining the semi-autonomous status of Fiume within the Habsburg Empire until the fall of the Austro-Hungarian Empire in 1918 – the longest-lasting known case of an actually implemented corpus separatum.
Maria Theresa of Austria, with her sovereign decision of 2 October 1776, gave up possession of Fiume, which was a hereditary fief of the Habsburgs within the Holy Roman Empire, and gave it to the Kingdom of Hungary, of which she was also Queen, with a view of fostering trade. Since Hungary proper was some 500 km away, the city was annexed to Croatia, whose territory began at the city walls. Croatia, as a kingdom, was united with Hungary and with it formed the “Lands of the Holy Crown of St Stephen”. Two and a half years later, Maria Theresa, as Queen of Hungary, by a royal rescript dated 23 April 1779, annexed the city of Fiume directly to Hungary as a corpus separatum (that is, not as a part of Croatia, which was in a personal union with Hungary). Since Fiume had to serve a similar function for Hungary as Trieste did for the Habsburg lands, the Hungarian estates (and probably the Queen) wanted to grant the City a similar degree of institutional autonomy to that already enjoyed by Trieste.