Defender of the Faith is one of the titles used by British sovereigns. In 1521, King Henry VIII wrote in defense of the Roman Catholic Church against the German Protestant reformer Martin Luther. As a reward, Pope Leo X gave Henry the title Fidei Defensor (Defender of the Faith), which he had requested. Ironically, Henry later broke with the Roman Catholic Church and became head of the Church of England. In 1544, the title Defender of the Faith was confirmed by Parliament for perpetual use by British sovereigns.
The title appears on some coins as Fid. Def. or F.D., abbreviations of the Latin words Fidei Defensor. In the royal title, the phrase Defender of the Faith comes immediately after Head of the Commonwealth.
See also Henry VIII.
