Born William Henry Pratt at 10 Hern Villas, Forest Hill Road (now 36 Forest Hill Road) on the edge of East Dulwich and almost facing the end of Peckham Park, Karloff can be said to have created the role of the screen horror character. Karloff, the youngest of nine children was only a baby when his father, a diplomat died. Probably Pratt senior was already in poor health when the family moved to Hern Villas, a new and attractive terrace occupied by lower-middle class residents and the reason for the move might have been to be near other family members; there were several residents named Pratt in nearby Friern Road.
Karloff's mother was no longer living in the house in 1902, by which time Hern Villas had been converted into shops, and she may have moved to the Enfield area. William, who went to Uppingham School and later studied at London University, was expected to follow his father into the diplomatic service but instead eloped to Canada in 1909 with Olive Wilton the first of his five wives. Taking work on farms to support himself and his wife he was later attracted to join a theatrical touring company with which he travelled over North America.
He had a dark skin tone probably inherited from his mother who had an East Indian heritage and to give his persona even greater mystery he adopted the Russian and romantic sounding stage name of Boris Karloff. In 1916, penniless and divorced he arrived in California seeking work and took a job with a cement company. Carrying the heavy sacks of cement apparently was the start of his back trouble which was to give him great discomfort throughout his life and which was later aggravated by the heavy brace he had to wear as part of his Frankenstein costume.
He made his screen debut in Hollywood in 1916 as screen extra in The Dumb Girl of Portici but his first break came three years later in the Douglas Fairbanks' movie His Majesty, The American . His appearance in this film led to a seven year contract with Universal and he had appeared in 80 films as a character actor before he got his first notice. Karloff was resigned to playing minor parts when in 1931, at the age of 44, he got the role which offered him stardom. The part of The Monster in the movie Frankenstein was initially offered to Bela Lugosi, the star of Dracula. Lugosi was unhappy with having a part in which his face would be unrecognisable through the heavy makeup and he had no lines to deliver. For Karloff, it was a physically demanding assignment but one which made him a star. However, in the first release of Frankenstein the screen credit for the role of the Monster was merely a question mark. It was in no small way because of Karloff's good natured and even personality that he continued to get on well with Lugosi after the film's release and they appeared in three movies including The Raven.
As the horror genre waned in the 1930's, Karloff was increasingly cast as a heavy in various gangster films like Howard Hughes' Scarface. By the 1940's Karloff was typecast as movie menace almost exclusively appearing in B movies. Frustrated by the roles he was being offered, Karloff turned his attention to helping to establish the Screen Actors Guild and returned to the Stage. He appeared on Broadway as the villainous Joseph Brewster in Arsenic and Old Lace and went on to appear in Priestley's The Linden Tree and The Lark for which he received a Tony award nomination.
Although he returned to Hollywood he was still cast in dreary low-budget films. He did better in this period on television with several series and numerous other appearances. A role for which he is fondly remembered is as the Narrator in Dr Seuss, The Grinch who stole Christmas. However his swan song in 1968 in Targets directed by Peter Bogdanovitch allowed Karloff to reprise his earlier stardom by playing an ageing horror-film actor. In this film Karloff gave his best performance in years. Since the early 1960's back pain and emphysema had increasingly taken their toll and he was obliged to use a wheelchair between 'takes'. He retired after Targets and lived in Midhurst, Sussex. He died in 1969.