List of shortest reigning monarchs of all time

Less than a year

*Vua Triệu Dương Vương, the fifth and last King of the Triệu Dynasty, Vietnam (111 BC)
*High King of Ireland Fogartach mac Néill, (several months in 724)
*Vua Hàm Nghi, the eighth Emperor of the Nguyễn Dynasty, Vietnam (2 August 1884 - July, 1885)
*Vua Hôn Đức Công, the eighth King of the Trần Dynasty, Vietnam (1369 - November, 1370)
*Vua Lý Chiêu Hoàng, the ninth and last ruler (and first Queen Regnant) of the Lý Dynasty, Vietnam ( October, 1224 - 21 October, 1225)
*Fuad II of Egypt (26 July 1952 - 18 June 1953)
*Vua Lệ Đức Hầu, the fourth King of the Later Lê Dynasty, Vietnam ( 7 October 1459 - 6 June, 1460)
*Vua Hồ Quý Ly, the first King of the Hồ Dynasty, Vietnam (February - ?, 1400)
*Vua Kiến Phúc, the seventh Emperor of the Nguyễn Dynasty, Vietnam (2 December, 1883 - 31 July, 1884)
*Edward VIII of the United Kingdom (20 January - 11 December 1936)
*Agustín I of Mexico (19 May 1822 – 19 March 1823)
*Louis I of Spain (slightly more than 7 months in 1724)
*Edmund Ironside, King of England (23 April - 30 November 1016)
*Vua Lê Túc Tông, the seventh King of the Later Lê Dynasty, Vietnam (6 June - 7 December, 1504)
*Christian VIII of Norway (1814)
*Lulach of Scotland (August 1057 - 17 March 1058)
*Duncan II of Scotland (May - November 1094)
*Harold Godwinson, King of England (6 January - 14 October 1066)
*Yuan Shikai, The Hongxian Emperor of China, (2 December 1915 - 22 March 1916)
*Vua Hiệp Hoà, the sixth Emperor of the Nguyễn Dynasty, Vietnam ( 30 July - 29 November, 1883)
*Frederick III, German Emperor (1888) 99 days
*Murad V Ottoman Sultan (93 days, 30 May - 31 August 1876)
*Peter IV of Portugal (about two and a half months, 10 March - 28 May 1826)
*Edward V of England (about two and a half months, 9 April - 25 June 1483)
*Edgar the Atheling, King of England October - December 1066.
*Prince Frederick Charles of Hesse-Kassel (or Hesse-Cassel), King of Finland (9 October - 14 December 1918)
*Chuǎng Wáng Emperor of the Shun Dynasty [China] (April 25 - May 27 1644)
*Umberto II of Italy (May 9 - June 12, 1946)
*Mindaugas II of Lithuania (11 July – 2 November 1918)
*William of Albania (7 March - 3 September, 1914)
*Habibullah Ghazi of Afghanistan (January 17 - October 13 1929)
*Eduard, Duke of Anhalt (April 21 - September 13 1918)
*Joachim Ernst, Duke of Anhalt (September 13 – November 12, 1918)
*Jamshid bin Abdullah of Zanzibar (July 1, 1963 - January 12, 1964)
*Louis XVIII of France (April 6, 1814 – March 20, 1815, later ruled from July 8, 1815 to September 16, 1824)
*Pope John Paul I (33 days, August 26 — September 28, 1978)
*Napoleon I of France (March 1 – June 22, 1815; previously ruled from March 20, 1804 to April 6, 1814)
*Vua Mạc Toàn, the sixth King of the Mạc Dynasty, Vietnam (1592)
*Jaya Harivarman II of Champa (1167)
*Jaya Indravarman V of Champa (1191)
*Charles II, Duke of Parma (17 December 1847 - 19 April 1848)
*Chúa Trịnh Cán, the tenth Lord of the Trịnh Lords, Vietnam (2 months in 1782)
*Sweyn Forkbeard, King of England for five weeks in 1013-1014.
*Constantine III , Byzantine emperor February, 641 – May, 641.
*Heraklonas, Byzantine emperor February, 641 – September, 641
*Alexius IV Angelus, Byzantine emperor, August 1 1203 - January 27-28 1204
*Alexios V Doukas, Byzantine emperor, February 5 – April 12, 1204
*Constantine Laskaris, Byzantine emperor, 1204
*Teia, last Ostrogothic king, 552
*Eraric,Ostrogothic king, 541
*Hildeprand, king of the Lombards, 744

Less than a month

"Note: Some of the following have been disputed as legitimate monarchs"
*Prince He of Changyi (27 days, 74 BC)
*Taichang Emperor of the Ming dynasty [China] (28 August - 26 September 1620)
*Constantine of Russia (1 - 25 December 1825)
*Jane Grey, Queen of England (10 - 19 July 1553)
*Henry V of France (2 - 9 August 1830)
*Milan Obrenović II, Prince of Serbia (25 June - 8 July 1839)
*Napoleon II of France (22 June – 7 July 1815)
*Louis II of Holland (10 days, 1810)
*Saad Al-Abdullah Al-Salim Al-Sabah of Kuwait (15 - 24 January 2006)
*Zimri of Israel (7 days, 885 BC)
*Gordian I of Roman Empire (22 March - 12 April 238)

Less than a week

*Otto Witte of Albania (5 days, 13 - 18 August 1913) (disputed)
*John I of France (5 days, 15 – 20 November 1316)
*Vua Lê Trung Tông (3 days, October 1005) , the second King of the Prior Lê Dynasty, Vietnam
*Vua Lê Quang Trị (3 days, 1516), the tenth Emperor of the Later Lê Dynasty, Vietnam
*Vua Dục Đức (2 days, 20 July - 22 July 1883), the fifth Emperor of the Nguyễn Dynasty, Vietnam
*Khalid bin Barghash of Zanzibar (2 days, 25 - 27 August 1896)
*Dipendra of Nepal (less than 56 hours, 1 - 4 June 2001)

Less than a day

"Due to the ephemeral nature of their reigns, the following have been disputed as legitimate monarchs:"

*Saul Wahl of Poland (18 August 1587) (may not have existed)
*Michael II of Russia (about sixteen hours; 15-16 March 1917)
*Phillipe VII of France (about sixteen hours; 28-29 February 1848)
*Emperor Modi of Jin (about 12 hours; 9 February 1234)
*Louis XIX of France (about twenty minutes on 2 August 1830)
*Luís Filipe I of Portugal (died twenty minutes after the assassination of his father; never crowned; 1 February 1908) [actually Prince Royal rather than Crown Prince, and so did not automatically assume title; see article]

ee also

* List of longest reigning current monarchs
* List of longest reigning monarchs of all time