Crown prince in the context of "Heir apparent"

An heir apparent is a person who is first in the order of succession and cannot be displaced from inheriting by the birth of another person. A person who is first in the current order of succession but could be displaced by the birth of a more eligible heir is known as an heir presumptive.

Today these terms most commonly describe heirs to hereditary titles (e.g. titles of nobility) or offices, especially when only inheritable by a single person. Most monarchies refer to the heir apparent of their thrones with the descriptive term of crown prince or crown princess, but they may also be accorded with a more specific substantive title: such as Prince of Orange in the Netherlands, Duke of Brabant in Belgium, Prince of Asturias in Spain (also granted to heirs presumptive), or the Prince of Wales in England and Wales; former titles include Dauphin in the Kingdom of France, and Tsesarevich in Imperial Russia.

Akihito (born 23 December 1933) is a member of the Imperial House of Japan who reigned as the 125th emperor of Japan from 7 January 1989 until his abdication on 30 April 2019. The era of his rule was named the Heisei era, Heisei being an expression of achieving peace worldwide.

Akihito was born as the fifth child and first son of Emperor Shōwa and Empress Kōjun. During the Second World War, he moved out of Tokyo with his classmates and remained in Nikkō until the surrender of Japan. In 1952, his Coming-of-Age ceremony and investiture as crown prince were held, and he began to undertake official duties in his capacity as crown prince. The next year, he made his first journey overseas and represented Japan at the coronation of Elizabeth II in London. He completed his university education in 1956. In April 1959, he married Michiko Shōda, a commoner; it was the first imperial wedding to be televised in Japan, drawing about 15 million viewers. The couple has three children: Naruhito, Fumihito, and Sayako.

Li Chongrun (Chinese: 李重潤; pinyin: Lǐ Chóngrùn; c.2 March 682 – October 8, 701), né Li Chongzhao (Chinese: 李重照; pinyin: Lǐ Chóngzhào), formally Crown Prince Yide (Chinese: 懿德太子; pinyin: Yìdé Tàizǐ ), was an imperial prince of the Tang dynasty and Wu Zetian's Zhou dynasty. He was the only son of Emperor Zhongzong (Li Zhe/Li Xian) and Emperor Zhongzong's second wife Empress Wei. In 701, he offended his grandmother Wu Zetian by discussing Wu Zetian's lovers Zhang Yizhi and Zhang Changzong with his sister Li Xianhui the Lady Yongtai and her husband Wu Yanji (武延基) the Prince of Wei, and he, along with Li Xianhui and Wu Yanji, were forced to commit suicide. He was posthumously honored as crown prince after his father Emperor Zhongzong was restored to the throne in 705 and in 706, Emperor Zhongzong provided Li Chongrun with an honorable burial by interring his remains at the Qianling Mausoleum.

Hirohito (裕仁; 29 April 1901 – 7 January 1989), posthumously honored as Emperor Shōwa (昭和天皇, Shōwa Tennō), was the 124th emperor of Japan according to the traditional order of succession, reigning from 1926 until his death in 1989. He remains the longest-reigning emperor in Japanese history and one of the longest-reigning monarchs in the world. As emperor during the Shōwa era, Hirohito presided over the rise of Japanese militarism, Japan's invasion of mainland Asia, the outbreak of the Second Sino-Japanese War, the Second World War, and the nation's postwar economic miracle.

Hirohito was born during the reign of his paternal grandfather, Emperor Meiji, as the first child of Crown Prince Yoshihito and Crown Princess Sadako (later Emperor Taishō and Empress Teimei). When Emperor Meiji died in 1912, Hirohito's father ascended the Chrysanthemum Throne, and Hirohito was proclaimed Crown Prince of Japan in 1916, making him the heir apparent. In 1921, he made an official visit to the United Kingdom and Western Europe, marking the first time a Japanese crown prince had traveled abroad. Due to his father's ill health, Hirohito became Sesshō of Japan (regent) that same year. In 1924, he married Princess Nagako Kuni, with whom he later had seven children: Shigeko, Sachiko, Kazuko, Atsuko, Akihito, Masahito and Takako. He became emperor upon his father's death in 1926.

The lordship of Piedmont, later the principality of Piedmont (Italian: Piemonte), was originally an appanage of the County of Savoy, and as such its lords were members of the Achaea branch of the House of Savoy. The title was inherited by the elder branch of the dynasty in 1418, at about which time Savoy was elevated to ducal status and Piedmont to princely status. When the House of Savoy was given the Kingdom of Sardinia, the Savoyards used the style of Prince of Piedmont (Italian: Principe di Piemonte) for their heir apparent. This first came into use by Prince Victor Amadeus of Savoy.

The usage was retained when Victor Emmanuel II became King of Italy, "Prince of Piedmont" becoming roughly equivalent to the British "Prince of Wales", the title bestowed to the Crown prince.

Princess is a title used by a female member of a regnant monarch's family or by a female ruler of a principality. The male equivalent is a prince (from Latin princeps, meaning principal citizen). Most often, the term has been used for the consort of a prince, or for the daughter of a monarch. A crown princess can be the heir apparent to the throne or the spouse of the heir apparent.

Princess Märtha of Sweden (Märtha Sofia Lovisa Dagmar Thyra; 28 March 1901 – 5 April 1954) was Crown Princess of Norway as the spouse of the future King Olav V from 1929 until her death in 1954. As Olav only became king in 1957, Märtha never became Queen of Norway. Her son, Harald V, is the current king of Norway. Princess Märtha was also an elder sister of Queen Astrid of Belgium and a maternal aunt of Grand Duchess Joséphine-Charlotte of Luxembourg and Kings Baudouin and Albert II of Belgium.

In 1940, Crown Princess Märtha and her family were immersed in World War II as Germany invaded Norway. After escaping to her home country of Sweden, and then being evacuated to America by President Franklin D. Roosevelt, she effectively advocated for Norway and did fundraising until the end of the war. In 1942, King Haakon VII of Norway, Märtha's father-in-law, invested her as a Dame Grand Cross of the Royal Norwegian Order of Saint Olav.

Margrethe II abdicated as Queen of Denmark on 14 January 2024, the 52nd anniversary of her accession, being the first voluntary abdication of a Danish monarch since that of Eric III in 1146.

Margrethe made the announcement of her abdication during her New Year's Eve address on 31 December 2023. On 14 January, Margrethe signed a declaration of her abdication during a meeting of the Council of State, whereafter her elder son Crown Prince Frederik succeeded to the Danish throne as King Frederik X. Per Danish state custom, the prime minister of Denmark then proclaimed the accession of the new monarch from the balcony of Christiansborg Palace.