Childhood and education (1544–1559)
Born eleven years after his parents' wedding, Francis was named for his grandfather, King Francis I and uncle. The long delay in producing an heir may have been due to his father's repudiation of his mother in favour of his mistress Diane de Poitiers, however this repudiation was negated by Diane's insistence that Henry spend his nights with Catherine. Francis was at first raised at the Château de Saint-Germain-en-Laye. He was baptised on 10 February 1544 at the Chapelle des Trinitaires in Fontainebleau. His godparents were Francis I (who knighted him during the ceremony), Pope Paul III, and his great-aunt Marguerite de Navarre. He became governor of Languedoc in 1546, and Dauphin of France in 1547, when his grandfather Francis I died.
Francis's governor and governess were Jean d'Humières and Françoise d'Humières, and his tutor was Pierre Danès, a Greek scholar originally from Naples. He learned dancing from Virgilio Bracesco and fencing from Hector of Mantua.
King Henry II, his father, arranged a remarkable betrothal for his son to Mary, Queen of Scots, in the Châtillon agreement of 27 January 1548, when Francis was only four years old. Mary had been crowned Queen of Scots in Stirling Castle on 9 September 1543 at the age of nine months following the death of her father James V. Besides being the queen of Scotland, Mary was a granddaughter of Claude, Duke of Guise, a very influential figure at the court of France. Once the marriage agreement was formally ratified, the six-year-old Mary was sent to France to be raised at court until the marriage. Although Mary was tall for her age and eloquent, her betrothed Francis was abnormally short and stuttered. Henry II commented that "from the very first day they met, my son and she got on as well together as if they had known each other for a long time".
On 24 April 1558, the fourteen-year-old Dauphin married the Queen of Scots in Notre Dame Cathedral in Paris. It was a union that could have given the future kings of France the throne of Scotland and also a claim to the throne of England through Mary's great grandfather, King Henry VII of England. As a result of the marriage, Francis became King Consort in Scotland until his death. The marriage produced no children, possibly due to Francis' illnesses or his undescended testicles.