Today is Boris Karloff day on TCM.

[trof]

He used to scare the pants off me when I was a kid.

Some interesting factoids courtesy of imdb.com:

Birth Name
William Henry Pratt

Nicknames
Billy
The Uncanny

Along with fellow actors Lon Chaney, Bela Lugosi and Vincent Price, Boris Karloff is recognized as one of the true icons of horror cinema, and the actor most closely identified with the general public's perception of the "monster" from the classic Mary Shelley book, "Frankenstein". William Henry Pratt was born on November 23, 1887, in Camberwell, London, England, the son of Edward John Pratt Jr., the Deputy Commissioner of Customs Salt and Opium, Northern Division, Indian Salt Revenue Service, and his third wife, Eliza Sarah Millard.

He was educated at London University in anticipation that he would pursue a diplomatic career; however, he emigrated to Canada in 1909 and joined a touring company based out of Ontario and adopted the stage name of "Boris Karloff." He toured back and forth across the USA for over ten years in a variety of low-budget theater shows and eventually ended up in Hollywood with very little money to his name. Needing cash to support himself, Karloff secured occasional acting work in the fledgling silent film industry in such pictures as The Deadlier Sex (1920), Omar the Tentmaker (1922), Dynamite Dan (1924) and Tarzan and the Golden Lion (1927), in addition to a handful of serials (the majority of which sadly haven't survived). Karloff supplemented his meager film income by working as a truck driver in Los Angeles, which allowed him enough time off to continue to pursue acting roles.

In contrast to the image he presented in most of his films, the private Karloff was, by every account, a quiet, bookish man off- screen. A true gentleman, he had many friends, both in and out of show business, and he was particularly fond of children. For the latter, among other things, he recorded many successful albums of children's stories.

His first Broadway play was "Arsenic and Old Lace" in a role that was written for him. He played Jonathan Brewster, whose face has been changed by a disreputable plastic surgeon named Dr. Einstein so that he now looks like Boris Karloff.
http://www.imdb.com/name/nm0000472/bio