 Thomas of Lancaster was taken to Pontefract Castle , which by then had fallen to the King . There he was submitted to what was little more than a show trial , and – in front of a gathering of earls and barons – sentenced to death . On 22 March 1322 , he was led out of the castle and beheaded in front of a jeering crowd . In the years to come , a cult emerged around the person of the late earl as a martyr , and even a possible saint . Lancaster had shown no signs of extraordinary piety or other personal abilities during his lifetime , and the cult has been interpreted as a reaction to the incompetent and oppressive reign of Edward II . 
