Apolitical union is a type ofpolitical entity which is composed of, or created from, smallerpolities or the process which achieves this. These smaller polities are usually calledfederated states andfederal territories in afederal government; they are calledprefectures,regions, orprovinces in the case of acentralised government. This form of government may be created through voluntary and mutualcession and is described asunionism[a] by its constituent members and proponents. In other cases, it may arise frompolitical unification, characterised bycoercion andconquest. The unification of separate states which, in the past, had together constituted a single entity is known asreunification.[2] Unlike apersonal union orreal union, the individualconstituent entities may havedevolution of powers but are subordinate to acentral government or coordinated in some sort of organization. In a federalised system, the constituent entities usually haveinternal autonomy, for example in the setup ofpolice departments, andshare power with the federal government, for whom externalsovereignty,military forces, andforeign affairs are usually reserved. The union isrecognised internationally as a single political entity. A political union may also be called a legislative union or state union.[3]A union may be effected in many forms, broadly categorized as:
In an incorporating union a new state is created, the former states being entirely dissolved into the new state (although some aspects may be preserved;see below).
Incorporating unions have been present throughout much of history, such as when:
Nevertheless, a full incorporating union may preserve the laws and institutions of the former states, as happened in the creation of the United Kingdom. This may be simply a matter of practice or to comply with a guarantee given in the terms of the union.[5] These guarantees may be to ensure the success of a proposed union (or in the least to prevent continuing resistance), as occurred in the union ofBrittany andFrance in 1532 (Union of Brittany and France) in which a guarantee was given for the continuance of laws and of theEstates of Brittany (a guarantee revoked in 1789 at theFrench Revolution).[6] The assurance that institutions are preserved in a union of states can also occur as states realize that, whilst a power imbalance exists (such as between the economic conditions of Scotland and England prior to theActs of Union 1707), it is not so great that it precludes the possibility for concessions to be made. TheTreaty of Union for creating the unifiedKingdom of Great Britain in 1707 contained a guarantee of the continuance of the civil laws and the existing courts in Scotland[7] (a continuing guarantee), which was significant for both parties. The Scottish, despite economic troubles during theSeven Ill Years preceding the union, still retained power to negotiate.[8]
This marks a delineation of states that are able to ensure preservation of interests: there has to be some mutually beneficial reasoning behind the formal or informal preservation of interests. In theUnion creating theUnited Kingdom of Great Britain and Ireland in 1801, no such guarantee was given for the laws and courts of theKingdom of Ireland, though they were continued as a matter of practice.[9] The informal recognition of such interests represents the different circumstances of the two Unions, the small base of institutional power in Ireland at the time (those who were the beneficiaries of theProtestant Ascendancy) had faced a revolution in theIrish Rebellion of 1798, and as a result there was an institutional drive toward unification, limiting the Irish negotiating power.[10] However, informal guarantees were given to preclude the possibility of further Irish unrest in the period following theFrench Revolution of 1789 and the 1798 rebellion. These types of informal arrangements are more susceptible to changes; for example,Tyrol was guaranteed that its Freischütz companies would not be posted to fight outside Tyrol without their consent, a guarantee later revoked by the Austrian state. However, this case can be contrasted with the continued existence of theScottish Parliament and a separate body ofScottish law distinct fromEnglish law.[11]
In an incorporating annexation a state or states is united to and dissolved in an existing state, whose legal existence continues.
Annexation may be voluntary or, more frequently, by conquest.
Incorporating annexations have occurred at various points in history, such as when:
Federal annexation occurs when a unitary state becomes a federated unit of another existing state, the former continuing its legal existence. The new federated state thus ceases to be a state in international law but retains its legal existence in domestic law, subsidiary to the federal authority.[13]
Prominent historicalfederal annexations include:
The unification of Italy involved a mixture of unions. The kingdom consolidated around theKingdom of Sardinia, with which several states voluntarily united to form theKingdom of Italy.[14] Others polities, such as theKingdom of the Two Sicilies and thePapal States, were conquered and annexed. Formally, the union in each territory was sanctioned by a popular referendum where people were formally asked if they agreed to have as their new rulerVittorio Emanuele II of Sardinia and his legitimate heirs.[15]
The unification of Germany began in earnest when theKingdom of Prussia annexed numerous petty states in 1866.[16]
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In addition to regional movements,supranational andcontinental unions that promote progressive integration between its members started appearing in the second half of the 20th century, first by theEuropean Union (EU). Other examples of such unions include theASEAN (Association of Southeast Asian Nations),[17][18] theAsia-Pacific Economic Cooperation Forum,[19] and thePacific Islands Forum.[20]
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The political position of theUnited Kingdom is often discussed,[21][22] as well as former states likeSerbia and Montenegro (2003–2006), theSoviet Union (1922–1991) and theUnited Arab Republic (1958–1961).
Lord Durham was widely regarded as one of the most important thinkers in the history of theBritish Empire's constitutional evolution. He articulated the difference between a full legislative union and afederation. In his1839Report, in discussing the proposed union ofUpper and Lower Canada, he says:
Two kinds of union have been proposed – federal and legislative. By the first, the separate legislature of each province would be preserved in its present form and retain almost all its present attributes of internal legislation, the federal legislature exercising no power save in those matters which may have been expressly ceded to it by the constituent provinces. A legislative union would imply a complete incorporation of the provinces included in it under one legislature, exercising universal and sole legislative authority over all of them in exactly the same manner as the Parliament legislates alone for the whole of the British Isles.[23]
However, unification is not merely voluntary. It requires a balance of power between two or more states, which can create an equal monetary, economic, social and cultural environment. Those states that are eligible to unify must also agree to a transition from anarchy, where there is no sovereignty above the state level, to hierarchy.
States can decide to enter a voluntary union as a solution for existing problems and to face possible threats, such as environmental threats for instance. The task of triggering a political crisis and to get the attention of the citizens toward the unification's necessity is in the hands of the elites. It rarely succeeds (with exceptions such as theOld Swiss Confederacy and theconfederation of the United States), and at times even leads to a forced unification (Italy, USSR), where the unified states are deeply unequal.
From a realist perspective, small states can unify in order to face strong states or to conquer weak ones. One of the reasons to seek unification to a stronger state besides a common threat can be a situation of negligence or ignorance on behalf of the weak state.[24]
According to a 1975 study byUniversity of Rochester political scientistWilliam Riker, unions were motivated by security threats.[25] However, in contrast to Riker,Ryan Griffiths, aSyracuse University political scientist, published a paper in 2010 in which he analyzed voluntary political unifications from 1816-2001 and found that while unifications have occurred without security threats, they have not taken place in the absence of a common language.[26]