Frederick V (Danish and Norwegian: Frederik V; 31 March 1723 – 14 January 1766) was King of Denmark and Norway and Duke of Schleswig-Holstein from 6 August 1746 until his death in 1766. A member of the House of Oldenburg, he was the son of Christian VI of Denmark and Sophie Magdalene of Brandenburg-Kulmbach.

Although the personal influence of Frederick was limited, his reign was marked by the progress of commerce and trade, and art and science prospered under his reign. Unlike his parents who were deeply devoted to Pietism, Frederick grew into a hedonist. As regent, he took part in the conduct of government by attending council meetings, but he was afflicted by alcoholism and most of his rule was dominated by able ministers who were influenced by the ideas of the Age of Enlightenment. His ministers marked his reign by the progress of commerce and the emerging industry. They also avoided involving Denmark-Norway in the European wars of his time. Although Frederick V wasn't personally interested in cultural affairs, his first wife was, and the public entertainment and freedom of expression that had been banned during his father's reign was again permitted.

Prince Frederick was born between 10 and 11 in the evening on 31 March 1723. He was the grandson of King Frederick IV of Denmark and Norway and the only son of Crown Prince Christian and Sophie Magdalene of Brandenburg-Kulmbach. Frederick was the last Danish prince to be born in the then antiquated and overextended Copenhagen Castle, which dated from the late 14th century, and had assumed a monstrous appearance and started to crumble under its own weight after several extensions. Demolition of the castle began in 1731 to make way for a more adequate royal residence, the vast Baroque style Christiansborg Palace, from where Frederick would eventually reign. The young prince was baptized the following day in the Crown Princess's Bedchamber by the royal confessor Christen Lemvig, and was named after his grandfather, King Frederick IV.

As the Crown Prince's only son, Frederick was destined to rule from birth. A younger sister died in infancy in 1724, and his only surviving sister, Princess Louise, was born in 1726. On 12 October 1730, King Frederick IV died and Frederick's father ascended the throne as King Christian VI. Frederick himself became Crown Prince at the age of seven.

Christian VI and Queen Sophie Magdalene were deeply devoted to Pietism, a movement within Lutheranism that combines its emphasis on biblical doctrine with an emphasis on individual piety and living a vigorous Christian life. As a consequence, Frederick was given a strictly religious upbringing. At the age of 7, he received his own royal household with the German nobleman Georg Wilhelm von Söhlenthal as his hofmeister. Söhlenthal was an ardent supporter of the Moravian Brethren, and his home was the center of the pietistic circles in Copenhagen. He shared a deep religious piety with the king, and for a time he was Christian VI's adviser on ecclesiastical matters. However, Söhlenthal did not succeed in influencing the spiritual development of the Crown Prince, as he was an overly gentle and weak character, and in 1738 he was dismissed from his position as hofmeister.

Frederick's education became rather deficient. In 1730 the king entrusted the significant and well-educated privy councillor Iver Rosenkrantz supervision of Crown Prince Frederik's upbringing, but this had no influence on the actual teaching. Rosenkrantz was a supporter of the traditional Lutheran orthodoxy, while Christian VI more and more became a proponent of Pietism and lost confidence in Rosenkrantz. The Crown Prince's education was therefore completely carried out in the German Pietist spirit that prevailed at court. Like his ancestors at the then primarily German-speaking court in Copenhagen, he only had a poor command of the Danish language, and knew German better than Danish all his life. None the less, his mother ironically referred to him as "Der Dänische Prinz" (literally The Danish Prince in German) because he occasionally spoke Danish. Apart from a certain interest in coin collecting, he only had modest cultural or intellectual interests.

Prince Frederick proved himself from an early age to have a completely different nature from his strict and somewhat gloomy parents. He was gentle and kind in nature, cheerful and accessible to everyone, and wanted to see his subjects happy. Unlike his secluded parents, who were rarely seen outside their palaces, he enjoyed spending time in public with people from all walks of life. Despite his upbringing in a strictly pietistic home, he was not himself gripped by pietism. Although certainly not unfamiliar with religious sentiments, Frederick grew into a hedonist who enjoyed the pleasures of life such as deer stalking, wine and women.

This hedonism, however, evolved to debauchery, and Frederick became well known for a libertine lifestyle marked by sexual licentiousness and alcoholism. With a group of other rakes, he would tour the city's taverns and brothels, to an extent that his father at one point considered having him declared legally decapacitated. The King's more prudent advisers, however, spoke against it, as it would legally be a violation of the King's Law (Latin: Lex Regia; Danish: Kongeloven), the absolutist constitution of Denmark and Norway from 1665. Furthermore, it would also compromise the monarchy to an unprecedented degree to admit that the future king was unfit to rule.