Herman Webster Mudgett, better known as H.H. Holmes, was born on May 16, 1861. He is infamous for being one of America's first serial killers and for his role in the notorious "Murder Castle," a hotel he designed and built in Chicago for the sole purpose of carrying out murders and disposing of his victims. Holmes was executed on May 7, 1896, after being convicted of numerous murders, although the exact number of his victims remains a subject of debate and mystery.