King Frederick V of Denmark and Norway (1723-1766) was the son of Christian VI of Denmark and Norway (1699-1746) and Sophia Magdalena of Brandenburg-Kulmbach (1700-1770). He first married Princess Louise of Great Britain, daughter of King George II and Caroline of Ansbach, and together they had five children, a sixth died at birth. Louise herself died in 1751, only eight years into their marriage. Frederick's second wife was Juliana Maria of Brunswick-Wolfenbüttel and their son was Frederick, Hereditary Prince of Denmark and Norway. He became Regent of Denmark in 1772 after a bitter divorce between his half-brother, King Christian VII, and Queen Caroline Mathilde, following their turbulent marriage during which the king displayed behaviour now thought to be schizophrenia.
For further examples of portraits of King Frederick V, see R. Walker, The Eighteenth and Early Nineteenth Century Miniatures in the Collection of Her Majesty The Queen, Cambridge, 1992, pp. 48-49, nos. 93 and 95.