An heir apparent or heiress apparent is a person who is first in line of succession and cannot be displaced from inheriting, except by death or a change in the rules of succession.
An heir presumptive or heiress presumptive, by contrast, is someone who is first in line to inherit a title but whose claim can be displaced at any time (in legal terms, is "subject to divestiture") upon the occurrence of one or more events or sets of events for which the system of inheritance allows, such as the birth of a more eligible heir.
Today these terms most commonly describe heirs to hereditary titles, particularly monarchies. They are also used metaphorically to indicate an "anointed" successor to any position of power, e.g., a political or corporate leader.
The phrase is only occasionally found used as a title, where it usually is capitalized ("Heir Apparent"). Most monarchies give (or gave) the heir apparent the title of Crown Prince or a more specific title, such as Prince of Orange in the Netherlands, Prince of Asturias in Spain, or Prince of Wales in the United Kingdom. See crown prince for more examples.
This article primarily describes the term heir apparent in a hereditary system regulated by laws of primogeniture—as opposed to cases where a monarch has a say in naming the heir.
Heir apparent versus heir presumptive 
In a hereditary system governed by some form of primogeniture, an heir apparent is easily identifiable as the person whose position as first in the line of succession is secure, regardless of future births. An heir presumptive, by contrast, can always be "bumped down" in the succession by the birth of somebody more closely related in a legal sense (according to that form of primogeniture) to the current title-holder.
The clearest example occurs in the case of a title-holder with no children. If at any time they produce children, they (the offspring of the title-holder) rank ahead of whatever more "distant" relative (the title-holder's sibling, perhaps, or a nephew or cousin) previously was heir presumptive.
Many legal systems assume childbirth is always possible regardless of age or health. In such circumstances a person may be, in a practical sense, the heir apparent but still, legally speaking, heir presumptive. Indeed, when Queen Victoria succeeded her uncle King William IV, the wording of the proclamation even gave as a caveat:
- "...saving the rights of any issue of his late Majesty King William IV, which may be born of his late Majesty's consort."
This provided for the possibility that William's wife, Adelaide of Saxe-Meiningen, was pregnant at the moment of his death—since such a (so-named posthumous) child, if born and regardless of the gender of the child, would have displaced Victoria from the throne. Adelaide was 44 at the time, so pregnancy was possible even if unlikely.
Daughters in male-preference primogeniture 
Daughters (and their lines) may inherit titles that descend according to male-preference primogeniture, but only in default of sons (and their heirs). That is, both female and male offspring have the right to a place somewhere in the order of succession, but when it comes to what that place is, a female will rank behind her brothers regardless of their ages or hers.
Thus, normally, even an only daughter will not be her father's (or mother's) heiress apparent, since at any time a brother might be born who, though younger, would be heir apparent. Hence, she is an heiress presumptive.
Women as heirs apparent 
In a system of absolute primogeniture that does not consider gender, female heirs apparent occur. Several European monarchies that have adopted such systems in the last few decades furnish practical examples. Crown Princess Victoria of Sweden and Princess Catharina-Amalia of the Netherlands are respectively the oldest children of Kings Carl XVI Gustaf and Willem-Alexander and are their heirs apparent. Princess Elisabeth of Belgium and Princess Ingrid Alexandra of Norway are both heirs apparent to their fathers (who are in each case heir apparent to their respective countries' thrones). Victoria was not heiress apparent from birth (in 1977), but gained the status in 1980 following a change in the Swedish Act of Succession. Her younger brother Carl Philip (born 1979) was thus heir apparent for a few months. It was reported in October 2011 that discussions would take place between the heads of government of the Commonwealth realms aimed at changing the rules of succession to the 16 thrones of Elizabeth II to give equal rights to females. Following the CHOGM meeting, which took place in Perth, Australia, between 28–30 October 2011, it was announced that the rule change had the unanimous backing of all 16 member nations. However, the effects would not be felt for many years since the first two heirs (Charles, Prince of Wales, and his son Prince William, Duke of Cambridge) are already eldest born children, and it has been claimed that the gender-equality changes would apply only to descendants of Prince William.
But even in legal systems that apply male-preference primogeniture, female heirs apparent are by no means impossible: if a male heir apparent dies leaving no sons but at least one daughter, then the eldest daughter would replace her father as heir apparent to whatever throne or title is concerned, but only when it has become clear that the widow of the deceased is not pregnant. Then, as the representative of her father's line she would assume a place ahead of any more distant relatives. Such a situation has not to date occurred with the English or British throne; several times an heir apparent has died, but each example has either been childless or left a son or sons. However, there have been several female heirs apparent to British peerages (e.g. Frances Ward, 6th Baroness Dudley, and Henrietta Wentworth, 6th Baroness Wentworth).
In one special case, however, England and Scotland had a female heir apparent. The Revolution settlement that established William and Mary as joint monarchs in 1689 only gave the power to continue the succession through issue to Mary II, eldest daughter of the previous king, James II. William, by contrast, was to reign for life only, and his (hypothetical) children by a wife other than Mary would be placed in his original place (as Mary's first cousin) in the line of succession – after Mary's younger sister Anne. Thus, although after Mary's death William continued to reign, he had no power to beget direct heirs, and Anne became the heir apparent for the remainder of William's reign. She eventually succeeded him as Queen of England, Scotland and Ireland.
Displacement of heirs apparent 
The position of an heir apparent is normally unshakable: it can be assumed they will inherit. Sometimes, however, extraordinary events—such as the death or the deposition of the parent—intervene.
People who lost heir apparent status 
- Parliament deposed James Francis Edward Stuart, the infant son of King James II & VII (of England and Scotland respectively) whom James II was raising as a Catholic, as the King's legal heir apparent—declaring that James had, de facto, abdicated— and offered the throne to James II's oldest daughter, the young prince's much older Protestant half-sister, Mary (along with her husband, Prince William of Orange). When the exiled King James died in 1701, his Jacobite supporters proclaimed the exiled Prince James Francis Edward as King James III of England and James VIII of Scotland; but neither he nor his descendents was ever successful in their bids for the throne.
- Crown Prince Gustav (later known as Gustav, Prince of Vasa), son of Gustav IV Adolf of Sweden, lost his place when his father was deposed and replaced by Gustav IV Adolf's aged uncle, the Duke Carl, who became Charles XIII of Sweden in 1809. The aged King Charles XIII did not have surviving sons, and Prince Gustav was the only living male of the whole dynasty (besides his deposed father), but the prince was never regarded as heir of Charles XIII, although there were factions in the Riksdag and elsewhere in Sweden who desired to preserve him, and, in the subsequent constitutional elections, supported his election as his great-uncle's successor. Instead, the government proceeded to have a new crown prince elected (which was the proper constitutional action, if no male heir was left in the dynasty), and the Riksdag elected first August, Prince of Augustenborg, and then, after the death of the latter, the Prince of Ponte Corvo (Marshal Jean-Baptiste Bernadotte).
- Prince Carl Philip of Sweden, at his birth in 1979, was heir apparent to the throne of Sweden. A year later a change in that country's succession laws instituted absolute primogeniture, and Carl Philip was supplanted as heir apparent by his elder sister Victoria.
Breaching legal qualification of heirs apparent 
In some jurisdictions, an heir apparent can automatically lose that status by breaching certain constitutional rules. Today, for example:
- a British heir apparent would lose this status if he became a Catholic or married a Catholic. According to The Act of Settlement, the loss of any place in the succession would persist even if he later renounced Catholicism or if his Catholic spouse were to pre-decease him. This is the only religion-based restriction on the heir-apparent. However, as of October 2011, the governments of the 16 commonwealth realms of which Elizabeth II is Queen have agreed to remove the restriction on marriage to a Catholic.
- a Crown Prince/Princess of Sweden would lose heir apparent status if they marry without approval of the monarch or, contrary to Swedish law, married the heir to another throne.
- a Dutch Prince or Princess of Orange would lose status as heir to the throne if he or she married without the approval of the Dutch parliament, or simply renounced the right.
- a Spanish Prince of Asturias would lose status if he married against the express prohibition of the monarch or the Cortes.
- a Belgian Crown Prince or Princess would lose heir apparent status if he or she married without the consent of the monarch, or became monarch of another country.
- a Danish Crown Prince or Princess would lose status if he or she married without the permission of the monarch. When the monarch grants permission for a dynast to enter marriage, he/she may set conditions that must be met for the dynast to gain/maintain a place in the line of succession; this also applies for Crown Princes/Princesses.
Heirs apparent who never inherited the throne 
Heirs apparent who predeceased the monarch 
Heirs apparent who were forced to abandon their claim 
|Heir apparent||Lived||Heir of||Forced out|
|Carlos, Prince of Asturias||1545–1568||Philip II of Spain||Arrested and imprisoned by his father; died in prison six months later|
|Yinreng||1674–1725||The Kangxi Emperor||Imprisoned for life by Kangxi for immorality and treason|
|Alexei Petrovich, Tsarevich of Russia||1690–1718||Peter the Great of Russia||Imprisoned by his father and forced to relinquish his claim. Died in prison|
|Crown Prince Sado of Joseon (Korea)||1735–1762||Yeongjo of Joseon (Korea)||His father forced him to commit suicide by locking him in a rice chest|
|Philip, Duke of Calabria||1747–1777||Charles III of Spain||Intellectually disabled; removed from the line of succession|
|Philippe, comte de Paris||1838–1894||Louis Philippe I of France||Declaration of the Second Republic on 24 February 1848|
|Luís Filipe, Prince Royal of Portugal||1887–1908||Carlos I of Portugal and the Algarves||Jointly assassinated with his father|
|Mohammad of Saudi Arabia||1910–1988||King Faisal ibn Abdul-Aziz||Forced to abdicate in 1965|
|Prince Carl Philip of Sweden||1979-||Carl XVI Gustaf of Sweden||Swedish succession laws were changed in 1980. Carl Philip was supplanted by his elder sister Victoria|
Heirs apparent of monarchs who themselves abdicated or were deposed 
|Heir apparent||Lived||Heir of||End of line/monarchy|
|James Francis Edward Stuart||1688–1766||James II of England||James II was deposed 11 April 1689 for being Catholic|
|Louis-Antoine, Dauphin and Duke of Angoulême||1775–1844||Charles X of France||Abdicated jointly with his father on 2 August 1830|
|Gustav, Prince of Vasa||1799–1877||Gustav IV Adolf of Sweden||Gustav's whole family was excluded from the line of royal succession on 10 May 1809 by the Riksdag of the Estates, after the deposition of Gustav IV Adolf.|
|Louis Napoléon, Prince Imperial||1856–1879||Napoleon III of France||Napoleon III was deposed 4 September 1870 by the forces of the Third Republic|
|Crown Prince William of Germany||1882–1951||Wilhelm II, German Emperor||Wilhelm was deposed by the German government on 9 November 1918|
|Alexei Nikolaevich, Tsarevich of Russia||1904–1918||Nicholas II of Russia||Nicholas abdicated on 2/15 March 1917 on behalf of both himself and his son. The monarchy was abolished 1 September 1917|
|Alfonso, Prince of Asturias||1907–1938||Alfonso XIII of Spain||Alfonso XIII was deposed by the formation of the Second Spanish Republic on April 14, 1931. Prince Alfonso renounced his claim on 21 June 1933 so he could marry a commoner|
|Otto von Habsburg, Crown Prince of Austria, Hungary, Croatia and Bohemia||1912–2011||Charles I of Austria||Austria and Hungary abolished the monarchy in 1918.|
|Vittorio Emanuele, Prince of Naples||1937-||Umberto II of Italy||Italy abolished the monarchy on 12 June 1946, after Umberto II had reigned 33 days|
|Leka, Crown Prince of Albania||1939-2011||Zog of Albania||Two days after Leka's birth, Mussolini's Italy invaded Albania on 7 April 1939 and sent the royal family into exile|
|Crown Prince Amedeo of Savoy, Duke of Aosta||1943-||Tomislav II of Croatia||Tomislav II abdicated October 12, 1943 due to the Armistice between Italy and Allied armed forces, when Amedeo was only two weeks old|
|Alexander, Crown Prince of Yugoslavia||1945-||Peter II of Yugoslavia||Peter II was deposed by Yugoslavia's Constituent Assembly on 29 November 1945|
|Crown Prince Reza Pahlavi II||1960-||The last Shah of Iran, Mohammad Reza Pahlavi||The Shah was overthrown by the Iranian Revolution on 11 February 1979|
|Pavlos, Crown Prince of Greece||1967-||Constantine II of Greece||Constantine II fled into exile shortly after Pavlos's birth, and the monarchy was abolished 1 June 1973|
|Paras, Crown Prince of Nepal||1971-||Gyanendra of Nepal||Gyanendra was deposed 28 May 2008 in favour of a republican government|
|Jasim bin Hamad bin Khalifa Al Thani||1978-||Hamad bin Khalifa Al Thani||Renounced his claim in 2003 in favor of his younger brother, Sheikh Tamim|
Heirs apparent as of 2013 
- Proclamations of Accessions of British Sovereigns (1547-1952)
- First Post – Commonwealth to support royal succession rule change
- "King James’ Parliament: The succession of William and Mary - begins 13/2/1689" The History and Proceedings of the House of Commons: volume 2: 1680-1695 (1742), pp. 255-77. Accessed: 16 February 2007.