This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (May 2008) This article is part of the Politics series Forms of government List of government types Androcracy Anarchy Aristocracy Bureaucracy Communist state Confederation Corporatocracy & Corpocracy Corporatism Consociationalism Demarchy Democracy Consensus Consociationalism Deliberative democracy Democratic socialism Totalitarian democracy Dictatorship of the proletariat Direct democracy Egalitarianism Futarchy Industrial Open source governance Participatory democracy People's Pure Representative democracy Parliamentary system Consensus government Westminster system Polyarchy Presidential system Semi-presidential system Despotism Dictatorship Autocracy & Autarchy Enlightened absolutism Military & Military junta Right-wing Stratocracy Authoritarianism Totalitarianism Empire Ethnic democracy Ethnocracy Fascism Corporative state Federation Feudalism Garrison state Gerontocracy Hierocracy Isocracy Interregnum Interrex Provisional government Kakistocracy Kratocracy Kleptocracy Kritocracy & Kritarchy Kyriarchy Logocracy Matriarchy, Gynaecocracy,

    Gynocracy, & Gynarchy Phallocracy, criticized      in radical feminism Mediocracy Meritocracy Minarchism & Night Watchman Monarchy Absolute monarchy Constitutional monarchy Despotism Duchy Grand Duchy Diarchy Enlightened absolutism Elective monarchy Hereditary monarchy Non-Sovereign Monarchy Popular monarchy Principality New Monarchs Self-proclaimed monarchy Regent Absolute Constitutional & Limited Diarchy & Co-Kingship Elective Nanny state Nation-state Monocracy Nomocracy Noocracy Ochlocracy & Mobocracy Oligarchy Panarchism Pantisocracy Parliamentary Patriarchy Plutocracy & Plutarchy Pornocracy Saeculum obscurum Police state Polyarchy Triarchy Tetrarchy Pentarchy Heptarchy Presidential Puppet state Republic Crowned Capitalist Constitutional Single Party Federal Parliamentary Federal Slave state Slavocracy Socialist state Sociocracy Squirearchy Stratocracy Sultanism Supranational union Synarchy Technocracy Thalassocracy Theocracy & Thearchy Islamic state Theodemocracy Timocracy Tribal Chiefdom Tyranny Unitary state Welfare state Politics portal v · d · e

Diarchy (or dyarchy), from the Greek δι- "twice" and αρχια, "rule", is a form of government in which two individuals, the diarchs, are the heads of state. In most diarchies, the diarchs hold their position for life and pass the responsibilities and power of the position to their children or family when they die. Diarchy is one of the oldest forms of government. Diarchies are known from ancient Sparta, Rome, Carthage as well as from Germanic and Dacian tribes. Several ancient Polynesian societies exhibited a diarchic political structure as well. Ranks in the Inca Empire were structured in moieties, with two occupants of each rank, but with different prestige, one hanan (upper) and one hurin (lower). In modern usage diarchy means a system of dual rule, whether this be of a government or of an organization. Such 'diarchies' are not hereditary. Examples of modern forms are the governments of San Marino, Andorra and Northern Ireland. The Montagu-Chelmsford reforms of British India prescribed a "dyarchy" of ministers who were individually responsible to the legislature1 The Australian Defence Organisation operates as a diarchy. San Marino is the most ancient of the two present countries that retain two diarchs, the Captains Regent, as heads of state. Andorra is the other country that retains two diarchs, known as Co-Princes. Contents 1 Current diarchies 1.1 San Marino 1.2 Andorra 1.3 Swaziland 2 Former diarchies 2.1 Roman Republic 2.2 Swedish monarchs 2.3 English, Scottish and Irish monarchs 2.4 Lithuanian monarchs 2.5 Classical Sparta 2.6 Spiritual & Temporal Kings 3 Other usage 3.1 Australian Defence Organisation 3.2 India 3.3 Northern Ireland 4 See also 5 References and notes Current diarchies San Marino Main article: Politics of San Marino

In the Republic of San Marino, the most ancient republic in the World, the Diarchs are called the Captains Regent. Every six months, the Council elects two Captains Regent to be the joint heads of state, and to serve a 6-month term. The foundational theory was to create a balance of power or, at least, reciprocal control. The practice of dual heads of state, as well as the frequent re-election of the same, are derived directly from the customs of the Roman Republic. The Council is equivalent to the Roman Senate; the Captains Regent, to the Consuls of ancient Rome. Andorra Main article: Politics of Andorra Andorra is a co-principality. The Diarchs are the President of France and the Bishop of Urgell. The current co-princes are Nicolas Sarkozy and Joan Enric Vives Sicília respectively. Swaziland The Kingdom of Swaziland is a diarchy in which the king (Ngwenyama) rules in conjunction with his mother the queen mother (Indlovukazi). In practice however, most power is vested in the king, though it is often argued that the giving of authority whole-sale to the royal male in this way is a neo-traditionalistic as opposed to truly traditional custom. Former diarchies Roman Republic

The Roman Republic was ruled by two consuls, elected each year and each holding a veto power over the other's actions. Swedish monarchs Erik and Alrik Yngvi and Alf Björn at Hauge and Anund Uppsale Eric the Victorious and Olof (II) Björnsson Eric the Victorious and Olof Skötkonung Halsten Stenkilsson and Ingold I Filip and Ingold II English, Scottish and Irish monarchs William III and Mary II Lithuanian monarchs The Lithuanian Grand Dukes typically selected submonarchs from their families or loyal subjects to assist controlling the Grand Duchy. However, the Grand Dukes remained superior. Vytenis (superior) and Gediminas Gediminas (superior) and an unknown duke of Trakai, presumably Gediminas's son. Algirdas (superior) and Kęstutis Jogaila (superior) and Kęstutis A slightly different system developed for a brief period after Vytautas became Grand Duke, where nominally Vytautas ruled together with Jogaila, who took the title of aukščiausiasis kunigaikštis (Supreme Duke), but he has not once used the title to take any action, and in general the powers invested in the title were not clearly stated in any documents, besides the Pact of Horodlo, which guaranteed that Jogaila would have to approve the selection of a Lithuanian Grand Duke. The title was not used by any other king of Poland after Jogaila. Vytautas (Grand Duke) and Jogaila (Supreme Duke) Švitrigaila (Grand Duke) and Jogaila (Supreme Duke) for a brief period, until Švitrigaila declared war on Poland Sigismund I of Lithuania (Grand Duke) and Jogaila (Supreme Duke) until Jogaila's death. Classical Sparta

Classical Sparta in ancient Greece was ruled by two kings who could veto one anothers actions, in addition Sparta had group of a officials known as Ephors and a council of elders. Spiritual & Temporal Kings Another common pattern of diarchy has one king in charge of spiritual matters and another, usually subordinate to the first, in charge of temporal or military matters. This pattern was followed in early Hungarian society by the spiritual kende and the military gyula. The Khazars were ruled by the spiritual khagan and the military bek. During the shogunate of Japan, the emperor held spiritual and nominal authority over the whole country, while the shogun held temporal authority. Other usage Australian Defence Organisation Main article: Australian Defence Organisation The Australian Defence Organisation (ADO) is an Australian Government organisation which consists of the Australian Defence Force (ADF) and the civilian Department of Defence personnel supporting the ADF. The Chief of the Defence Force and the Secretary of the Department of Defence jointly manage the ADO under a "diarchy", a term used to describe the relationship between the Chief of the Defence Force and the Secretary, both of whom report directly to the Minister for Defence. The ADO diarchy is a governance structure unique in the Australian Commonwealth public service. India This section may be confusing or unclear to readers. Please help clarify the section; suggestions may be found on the talk page. (December 2009)

Due to shaky coalition governments in the recent past, Diarchies have been both successfully and unsuccessfully tested in India. Some successful examples include the current government in Jammu and Kashmir and Karnataka. A failed one was in 1995 in Uttar Pradesh between the BSP and the BJP. A diarchy condition was introduced by Indian Council Act 1919 in Montagu-Chelmsford Report. Introduction of Dyarchy in India : On 20th August 1917 in the House of Commons, the newly appointed Secretary of State, Lord Montague made a declaration and it was called "Grand Declaration". It said that the British policy was "increasing association of Indians in every branch of the administration and the gradual development of self-governing institutions with a view to progressive realization of responsible government in British India as an integral part of the British Empire". IN Pursuance of the policy laid down in the announcements by Lord Montague, the Secretary of State and Chelmsford, the Viceroy of India made an extensive tour of India in 1917-18 and a report called Montague - Chelmsford Report containing recommendations which paves the way for Government of India Act, 1919.

This act of 1919 introduced dyarchy or dual Government in the provinces. In the provinces, the executive was to be headed by a Governor who was appointed by the Secretary of State and in doing so he might consult the governor general. The Governor was responsible to the Secretary of State for acts of omission and commission. He was to maintain law and order in the province and ensure that provincial administration worked smoothly. In respect of transferred subjects, he was to be assisted by his ministers where as reserved subjects were to be administered by the Governor and his Executive Council. The members of the Executive council were to be appointed by Secretary of State and were responsible to him in all matters. There were certain matters which he was to administer at his own discretion. In such matters he was responsible to the Secretary of State. Each councillor was to remain in office for a period of 4 years. Their salaries and service conditions were not subject to the vote of provincial legislature. All decisions in the council were to be taken by a majority of votes and in case of need the Governor could use his casting vote. Northern Ireland Main article: First Minister and deputy First Minister

The positions First Minister and deputy First Minister operate as a diarchy and have done so since 1998. The devolved government of Northern Ireland established after the Belfast Agreement in 1998 has a system whereby the Assembly elects two leaders, one from each of the two main communities. These two leaders actually have identical powers even though they are called First Minister and deputy First Minister respectively and serve jointly. See also Monarchy Monarch Duumvirate References and notes ^ Dyarchy, Encyclopedia Britannica.

The positions First Minister and deputy First Minister operate as a diarchy and have done so since 1998. The devolved government of Northern Ireland established after the Belfast Agreement in 1998 has a system whereby the Assembly elects two leaders, one from each of the two main communities. These two leaders actually have identical powers even though they are called First Minister and deputy First Minister respectively and serve jointly. See also Monarchy Monarch Duumvirate References and notes ^ Dyarchy, Encyclopedia Britannica.