Frederick Sadleir Brereton (5 August 1872 – 12 August 1957) was a decorated soldier and an author of children's books on heroic deeds conducted in the name of the British Empire. Brereton was a prolific author. By the time he died he had written over 40 books.
Brereton served in the RAMC during the First World War. In 1919 he was appointed as a Commander of the Portuguese Order of Aviz.