Interregnum

An interregnum (plural interregna or interregnums) is a period of discontinuity of a government, organization, or social order. Archetypally, it was the period of time between the reign of one monarch and the next (coming from Latin inter-, "between" + rēgnum, "reign" [from rex, rēgis, "king"]), and the concepts of interregnum and regency therefore overlap. An interregnum can simplistically be thought of as a "gap", although the idea of an interregnum emphasizes the relationship to what comes before and to what comes after in a sequence. This contrasts with a near synonym like gap, which may be random, encompassing neither connotation of interjacency in a sequence nor formal interrelation.

Examples of interregna are periods between monarchs, between popes, between emperors of the Holy Roman Empire, between kings in an elective monarchy, or between consuls of the Roman Republic. The term can also refer to the period between the pastorates of ministers in some Protestant churches.

In Roman law, interregnum was usually accompanied by the proclamation of justitium (or state of exception, as did Giorgio Agamben demonstrate in his eponymic book - 2005). This is not surprising, as when a sovereign died - or when the Pope died - tumultus (upheavals) usually accompanied the news of a sovereign's death. Progressively, justitium came to signify the public mourning of the sovereign, and not anymore justitium, auctoritas being (mythically) attached to the physical body of the sovereign.

Historical periods of interregnum
Particular historical periods known as interregna include:


 * The 575–585 period in the Kingdom of Lombards.
 * The 840–843 period in the Carolingian Empire
 * The 1022-1072 period in Ireland, between the death of Máel Sechnaill mac Domnaill and the accession of Toirdhealbhach Ua Briain, is sometimes regarded as an interregnum, as the High Kingship of Ireland was disputed throughout these decades. The interregnum may even have extended to 1121, when Toirdhealbhach Ua Conchobhair acceded to the title.
 * The Great Interregnum (1254-1273 period) in the Holy Roman Empire between the end of Hohenstaufen rule and the beginning of Habsburg rule.
 * First Interregnum 1290-1292 in Scotland
 * Second Interregnum 1296-1306 in Scotland
 * The 1332-1340 period in Denmark when the country was mortgaged to a few German counts.
 * The 1383-1385 Crisis in Portugal
 * The 1402-1413 Ottoman Interregnum
 * The 1453-1456 in Kingdom of Majapahit (now in Java, Indonesia)
 * The 1481–1483 in Norway
 * The Time of Troubles in Russia (1598–1613) between the Rurikid and Romanov dynasties
 * The English Interregnum from 1649–1660 was a republican period in Britain, comprising the Commonwealth and the Protectorate of Oliver Cromwell after the regicide of Charles I and before the restoration of Charles II
 * A second English interregnum occurred between 23 December 1688, when James II was deposed in the Glorious Revolution, and the installation of William III and Mary II as joint sovereigns on 13 February 1689 pursuant to the Declaration of Right.

In some monarchies, such as the United Kingdom, an interregnum is usually avoided due to a rule described as "the king is dead, long live the King", i.e. the heir to the throne becomes a new monarch immediately on his predecessor's death or abdication. This famous phrase signifies the continuity of sovereignty, attached to a personal form of power named Auctoritas. This is not so in other monarchies where the new monarch's reign begins only with coronation or some other formal or traditional event. In the Polish-Lithuanian Commonwealth for instance, kings were elected, which often led to relatively long interregna. During that time it was the Polish primate who served as an interrex (ruler between kings).

Pope's interregnum (or sede vacante)
An interregnum occurs also upon the death of the Pope, though this is generally known as a sede vacante (vacant seat). The interregnum ends immediately upon election of the new Pope by the College of Cardinals.

Japanese era names
The Japanese era name or nengō system which was introduced in reign of Emperor Kōtoku was abandoned at the end of his reign; and the nengō was not updated for a quite some time, except for very brief re-occurrence near the close of Emperor Temmu's reign.

During the nearly half-century after Emperor Kōtoku, the reigning sovereigns were
 * Saimei-tennō (斉明天皇)
 * Tenji-tennō (天智天皇)
 * Kōbun-tennō (弘文天皇)
 * Temmu-tennō (天武天皇)
 * Jitō-tennō (持統天皇)
 * Mommu-tennō (文武天皇).

The first year of Emperor Mommu's rule (文武天皇元年; 686) could be arguably abbreviated as "the first year of Mommu" (文武元年; 686), but this is nowhere understood as a true nengō. The reigns of Japanese emperors and empresses are not nengō, nor were the two considered to be the same until Meiji came on the scene.

References to the emperors of Japan who ruled during this period are properly written as, for example,
 * "the 3rd year of Mommu" (文武天皇３年), and
 * not "Mommu 3" (文武３年).

Nengō were abolished during the interregnum years between Hakuchi and Shuchō, and again between Shuchō and Taihō. Near the mid-point of his reign, Emperor Mommu caused the now-conventional nengō chronologic system to be reinstated, and it has continued uninterrupted through today.


 * The two interregnum periods in the pre-Tahiō years are:


 * Taika era, 645-650
 * Hakuchi era, 650–654
 * interregnum/gap, 654-686
 * Saimei period, 655-662
 * Tenji period, 662-672
 * Kōbun period,672-673
 * Temmu period, 673-686
 * Shuchō era, 686
 * interregnum/gap, 686-701
 * Jitō period, 686-697
 * Mommu period, 697-701
 * Taihō era, 701-704

The broader utility of the Japanese nengō system is demonstrated by the use of a congruent device to parse non-nengō periods, including these late 7th century interregnum years between Taika and Taihō.

As an illustration: In the initial paragraph of its web page introduction to the history of Japanese calendars, the Japanese National Diet Library explains that "Japan organized its first calendar in the 12th year of Suiko (604)." See web site of the National Diet Library, "The Japanese Calendar" -- link to historical overview plus illustrative images from library's collection.