<P> A large United Kingdom of the Netherlands was formed for the Prince of Orange, including both the old United Provinces and the formerly Austrian - ruled territories in the Southern Netherlands . Other, less important, territorial adjustments included significant territorial gains for the German Kingdoms of Hanover (which gained East Frisia from Prussia and various other territories in Northwest Germany) and Bavaria (which gained the Rhenish Palatinate and territories in Franconia). The Duchy of Lauenburg was transferred from Hanover to Denmark, and Prussia annexed Swedish Pomerania . Switzerland was enlarged, and Swiss neutrality was established . Swiss mercenaries had played a significant role in European wars for a couple of hundred years: the Congress intended to put a stop to these activities permanently . </P> <P> During the wars, Portugal had lost its town of Olivença to Spain and moved to have it restored . Portugal is historically Britain's oldest ally, and with British support succeeded in having the re-incorporation of Olivença decreed in Article 105 of the Final Act, which stated that the Congress "understood the occupation of Olivença to be illegal and recognized Portugal's rights". Portugal ratified the Final Act in 1815 but Spain would not sign, and this became the most important hold - out against the Congress of Vienna . Deciding in the end that it was better to become part of Europe than to stand alone, Spain finally accepted the Treaty on 7 May 1817; however, Olivença and its surroundings were never returned to Portuguese control and this question remains unresolved . Great Britain received parts of the West Indies at the expense of the Netherlands and Spain and kept the former Dutch colonies of Ceylon and the Cape Colony as well as Malta and Heligoland . Under the Treaty of Paris, Britain obtained a protectorate over the United States of the Ionian Islands and the Seychelles . </P> <P> The Congress of Vienna was frequently criticized by 19 - century and more recent historians for ignoring national and liberal impulses, and for imposing a stifling reaction on the Continent . It was an integral part in what became known as the Conservative Order, in which the liberties and civil rights associated with the American and French Revolutions were de-emphasized, so that a fair balance of power, peace and stability, might be achieved . </P> <P> In the 20th century, however, many historians came to admire the statesmen at the Congress, whose work prevented another widespread European war for nearly 100 years (1815--1914). Among these is Henry Kissinger, who in 1954 wrote his doctoral dissertation, A World Restored, on it . Historian Mark Jarrett argues that the Congress of Vienna and the Congress System marked "the true beginning of our modern era". He says the Congress System was deliberate conflict management, and was the first genuine attempt to create an international order based upon consensus rather than conflict . "Europe was ready," Jarrett states, "to accept an unprecedented degree of international cooperation in response to the French Revolution ." Historian Paul Schroeder argues that the old formulae for "balance of power" were in fact highly destabilizing and predatory . He says the Congress of Vienna avoided them and instead set up rules that produced a stable and benign equilibrium . The Congress of Vienna was the first of a series of international meetings that came to be known as the Concert of Europe, which was an attempt to forge a peaceful balance of power in Europe . It served as a model for later organizations such as the League of Nations in 1919 and the United Nations in 1945 . </P>

Who hosted the treaty of vienna in 1815