Duke of Edinburgh, named after the city of Edinburgh, Scotland, is a title that has been created four times for members of the British royal family since 1726. The current holder is Prince Philip, consort(husband) of Queen Elizabeth II.
The title was created for a fourth time on 19 November 1947 by King George VI, who bestowed it on his son-in-law Lieutenant Philip Mountbatten, when he married Princess Elizabeth.
Subsequently, Elizabeth was primarily known as HRH Princess Elizabeth, Duchess of Edinburgh until she became Queen in 1952. The subsidiary titles of the dukedom were Earl of Merioneth and Baron Greenwich, of Greenwich in the County of London.
Like the dukedom, these titles were also in the Peerage of the United Kingdom. Earlier that year, Philip had renounced his Greek and Danish royal titles (he was born a Prince of Greece and Denmark, being a male-line grandson of King George I of Greece and male-line great-grandson of King Christian IX of Denmark) along with his rights to the Greek throne.
In 1957, Philip became a Prince of the United Kingdom.(Wiki)