Lloyd Alexander was born in Philadelphia, PA on January 30, 1924, and was raised in Drexel Hill, PA. During World War II he enlisted in the U.S. Army and was stationed in Wales, where he first encountered the region's myths and legends that would go on to influence his fantasy novels. At the end of the war, he worked in counterintelligence in Paris, where he met his future wife Janine Denni. The two married in 1946. Denni died in May 2007, shortly before Alexander's own death at his home in Drexel Hill on May 17, 2007.

Alexander was a renowned fantasy writer whose career spanned over 4 decades. His most renowned work was the cycle of five novels "The Chronicles of Prydain", published between 1964 and 1968, and which was set in a mythical kingdom inspired by the images and stories of Welsh mythology and Arthurian legend. The Prydain books include The Book of Three (1964), The Black Cauldron (1965), The Castle of Llyr (1966), and Taran Wanderer (1967). The last book in the series, The High King (1968), won the 1969 Newbery Award. The first two Prydain books were adapted into the Disney animated film The Black Cauldron in 1985.

Alexander, whose career has been compared by some to that of J. R. R. Tolkien, wrote over 40 books, starting with the semi-autobiographical And Let The Credit Go (1955). Other notable works of his include Time Cat: The Remarkable Journeys of Jason and Gareth (1963); The Marvelous Misadventures of Sebastian (1970), which won the 1971 National Book Award; the Westmark trilogy, Westmark (1981), which won a National Book Award in 1982, The Kestrel (1982), and The Beggar Queen (1984); and the Vesper Holly novels (1987-2005).