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.

Modern examples of diarchies are the Principality of Andorra, whose heads of state are the President of France and the Bishop of Urgell, and the Kingdom of Swaziland, where the joint heads of state are the king and his mother.


Current diarchies


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.


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 wholesale 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

English, Scottish and Irish monarchs

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.

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.

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 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.

Other usage

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 :

On 20 August 1917 in the House of Commons, the newly appointed Secretary of State, Lord Montague made the "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 produced the Montague - Chelmsford Report containing recommendations which paved 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 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.

Northern Ireland

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.

Diarchies in Popular Culture

  • The nation of Equestria from the popular animated TV show My Little Pony: Friendship is Magic operates, or at least used to, under a diarchy between the day princess Celestia and her younger sister Luna, the night princess.[1]

See also

References and notes

  1. ^ [1],MLP:FiM Episode 1.

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Diarchy — Di arch*y, n. [Gr. di = di s twice + ? to rule.] A form of government in which the supreme power is vested in two persons …   The Collaborative International Dictionary of English

  • diarchy — [dī′är΄kē] n. pl. diarchies [ DI 1 + ARCHY] government shared by two rulers, powers, etc …   English World dictionary

  • diarchy — variant of dyarchy …   New Collegiate Dictionary

  • Diarchy — Diarchie La diarchie est une forme de gouvernement où deux dirigeants règnent en position égale sur une société. Sparte, Rome, Carthage, l empire germanique, l Inde et des tribus daciennes ont été des diarchies. Les gouvernements d Andorre et de… …   Wikipédia en Français

  • diarchy — diarchial, diarchic, adj. /duy ahr kee/, n., pl. diarchies. government in which power is vested in two rulers or authorities. Also, dyarchy. [1825 35; DI 1 + ARCHY] * * * …   Universalium

  • diarchy — noun A form of government where power is shared between two joint authorities …   Wiktionary

  • diarchy — government by two people Forms of Government …   Phrontistery dictionary

  • diarchy — n. government with two rulers …   English contemporary dictionary

  • diarchy — [ dʌɪα:ki] (also dyarchy) noun (plural diarchies) government by two independent authorities. Derivatives diarchal adjective diarchic adjective Origin C19: from di 1 + Gk arkhia rule , on the p …   English new terms dictionary

  • diarchy — di•ar•chy or dyarchy [[t]ˈdaɪ ɑr ki[/t]] n. pl. chies gov a government in which power is vested in two rulers or authorities • Etymology: 1825–35 …   From formal English to slang

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.