Oszkár I (Paris, July 4, 1799 - Stockholm, July 8, 1859) was the king of Sweden and Norway, which had been in personal union with him since 1814, from 1844 until his death. He was the second ruler of the House of Bernadotte. After his accession to the throne, he supported many reforms and his ruling style was characterized by paternalism. After the events of 1848, his way of thinking became increasingly conservative, especially on constitutional issues. His foreign policy was characterized by anti-Russian. His father was Jean Baptiste Bernadotte, general of the French Revolution, marshal of France, and later, from 1818, king of Sweden (as John Charles XIV) and of Norway (as John Charles III). His mother was Désirée Clary, the former fiancee of French Emperor Napoleon. He was born as the only child of his parents. His godfather became Napoleon himself. He ascended the throne in 1844 after his father's death. After his accession to the throne, he supported many reforms. His initial liberalism and views on tax policy, freedom of the press, and criminal law reform coincided with the need for political change and the demands of industrialization. In addition to these, he took the first step towards achieving gender equality, when he passed the law in 1845, which stated that male and female heirs (siblings) benefit equally from the inheritance, if the deceased did not leave a will. He abolished the guild system in 1846. In his legislation, he took into account the aspect of increasing the wealth of his countries. In 1857, the Swedish parliament declared that none of his predecessors had been able to provide such prosperity to his subjects. Oszkár was a supporter of the union of the Scandinavian states, and as such he granted the two countries in the personal union, Norway and Sweden, the same rights, creating equality between the two countries. 1823. on June 19, he married Princess Jozefina of Leuchtenberg (1807–1876), born Joséphine Maximilienne de Beauharnais, daughter of Eugène de Beauharnais and Augusta Amália, Royal Princess of Bavaria, granddaughter of Joséphine de Beauharnais, Napoleon's first wife, who was also Mikasa I he was also the grandson of the king of Bavaria. The following children were born from their marriage: Károly Lajos Jenő (1826–1872), later XV. King of Sweden and Norway under the name Károly. Oszkár Ferenc Gusztáv, Duke of Uppland (1827–1852). Frigyes Oszkár (1829–1907), later II. King of Sweden and Norway under the name Oszkár. Royal Princess Sarolta Eugénia Augusta of Sweden (1830–1889). Ágost Károly Miklós, Duke of Dalarna (1831–1873). To King Charles of Sweden.

Oscar I was king of Norway and Sweden from 1844 to 1859. He was the second monarch of the House of Bernadotte and supported many reforms such as tax policy, freedom of the press, criminal law reform, and improvements in public education. During his reign, the Swedish and Norwegian mints also developed and new coins were introduced. The first 1/16 thaler appeared in the Swedish mint in 1844, 1/32 thaler in 1845, 2 skilling banco in 1846, 1849- in 4 skilling banco, in 1855 the first 1/4 riksdaler banco, in 1857 the 1/2 riksdaler banco and in 1858 the first 1 riksdaler banco coin. In Norwegian coinage, the first 1/2 speciedaler appeared in 1844, the 1/5 speciedaler in 1845, the first 1/2 skilling in 1848, the 1/4 speciedaler in 1850, the first 2 skilling in 1851, In 1855 the 1/3 speciedaler, in 1857 the first 1/8 speciedaler and in 1858 the 1 speciedaler coin. The portrait and coat of arms of King Oskar I appeared on the Swedish and Norwegian coins.