British prince

The title of Prince of the United Kingdom is granted by its sovereign—the reigning king or queen—who is the fount of all honours, and is conferred through the issuing of letters patent as an expression of the royal will. Individuals holding the title of prince will usually also be granted the style of Royal Highness. When a British prince is married, his wife, if not already a princess in her own right, gains the privilege of sharing in her husband's princely title and the dignity of being known as a British princess in his name. For example, the wife of Prince Michael of Kent is known as Princess Michael of Kent, and, Catherine, Duchess of Cambridge is entitled to refer to herself as a Princess of the United Kingdom.

Prior to 1714, the title of prince and the style of HRH was not customary in usage. Sons and daughters of the sovereign were not automatically or traditionally called a prince or princess. An exception was the Prince of Wales, a title conferred on the eldest son of the sovereign since the reign of Edward I of England. While in the Kingdom of Scotland, even though an honorific principality was created by James I, the heir-apparent was only referred to as Duke of Rothesay. Some others include John, brother of Richard the Lionheart and later King John, who is sometimes called Prince John.

After the accession of George I, it became customary for the sons of the sovereign and grandsons of the sovereign in the male line to be titled 'Prince' and styled His Royal Highness (abbreviated HRH). Great-grandsons of the sovereign were princes styled His Highness (abbreviated HH).

Just three weeks after the birth of her fourth grandchild but first male-line grandson, Queen Victoria issued letters patent in 1864 which formally confirmed the practice of calling children and male-line grandchildren His Royal Highness with their titular dignity of Prince or Princess prefixed to their respective Christian names. The letters patent did not address the styling of great grandchildren or further descendants as His/Her Highness or Prince or Princess. However, the only living male person of this type was Prince Ernest Augustus (age 19). Prince Ernest's Kingdom of Hanover was abolished in 1866, but he was made a Duke of the United Kingdom and a Knight of the Garter in 1878, a major general in the British army in 1886, a lieutenant general in 1892 and general in 1898. At no point until World War I was his status as a British prince, based on being a great grandson of the sovereign, questioned.

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