Editing Oscar II (section)

==Early life==
[[File:Framsida av medalj med bild av Karl XV, Prins Gustaf och Oscar II i profil, 1829 - Skoklosters slott - 99618.tif|thumb|left|[[Mauritz Frumerie]]'s 1829 medal showing the three eldest sons of [[Oscar I of Sweden|Crown Prince Oscar]]: [[Charles XV|Charles]], [[Prince Gustaf, Duke of Uppland|Gustaf]], and Oscar.]]
Oscar Fredrik was born at the [[Stockholm Palace|Royal Palace]] in [[Stockholm]] on 21 January 1829, the third of four sons of [[Oscar I of Sweden|Crown Prince Oscar]] and [[Josephine of Leuchtenberg]].<ref name=Neveus>{{Cite encyclopedia |first=Torgny |last=Nevéus |title=Oscar II |url=https://sok.riksarkivet.se/sbl/Presentation.aspx?id=7812 |year=1992–1994 |encyclopedia=[[Svenskt biografiskt lexikon]] |volume=28 |pages=377 |language=sv |access-date=5 May 2024}}</ref> Upon his birth, he was created [[Duke of Östergötland]]. At birth, he was fourth in the [[succession to the Swedish throne]] after his father and older brothers, but as a younger son had no immediate prospect of inheriting the throne. During his childhood, he was placed in the care of the royal governess, Countess Christina Ulrika Taube.<ref>Gustaf Elgenstierna, Den introducerade svenska adelns ättartavlor. 1925–36.</ref>

Prince Oscar entered the [[Swedish Navy|Royal Swedish Navy]] as a midshipman at the age of 11, and was appointed junior lieutenant in July 1845. Later, he studied at [[Uppsala University]], where he distinguished himself in mathematics.{{sfn|Chisholm|1911}} On 13 December 1848, was made an honorary member of the [[Royal Swedish Academy of Sciences]].

On 6 June 1857, Prince Oscar married [[Sophia of Nassau|Princess Sophia of Nassau]] at the [[Biebrich Palace]], the ducal residence of the [[Duchy of Nassau]], with whom he had four sons. Princess Sophia was the youngest daughter of [[Wilhelm, Duke of Nassau]] and [[Princess Pauline of Württemberg (1810–1856)|Princess Pauline Friederike Marie of Württemberg]], and a half-sister of [[Adolphe, Grand Duke of Luxembourg|Adolphe]], the then reigning [[Duke of Nassau]] and future [[Grand Duke of Luxembourg]].<ref name=Neveus/>

[[File:King Charles XV of Sweden and Prince Oscar with Adjutants.jpg|thumb|left|Aides [[Daniel Nordlander]] (upper left) and [[Fritz von Dardel]], Ordnance Officer [[Ferdinand-Alphonse Hamelin]], [[General]] [[Henri-Pierre Castelnau]], King [[Charles XV of Sweden]] and Prince Oscar, future King Oscar II of Sweden, at the [[International Exposition (1867)|1867 International Exposition]] in [[Paris]], [[France]].]]
Upon the death of his father, King Oscar I, in 1859, Prince Oscar became [[heir presumptive]] to the thrones of Sweden and Norway, as his eldest brother King [[Charles XV of Sweden|Charles XV of Sweden/Charles IV of Norway]] was without a legitimate heir, having lost his only son, [[Prince Carl Oscar, Duke of Södermanland]], to [[pneumonia]] in 1854. His second elder brother, [[Prince Gustaf, Duke of Uppland]], had died of [[typhoid fever]] already in 1852.