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 legislature. 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.
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.
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.
English, Scottish and Irish 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.
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.
Spiritual and 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.
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.
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 diarchy in India :
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 four 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.
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 (unionist and nationalist). These two leaders actually have identical powers even though they are called First Minister and deputy First Minister respectively and serve jointly.
References and notes
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