Historically, Lady Salisbury would suffer one of the worst be-headings in history in which it took 11 strokes of the ax to finally do the job.
Lady Salisbury is condemned because she is a member of the Plantagenent Family, and a family flag is found at her castle. Kate O'Toole is the daughter of actor Peter O'Toole who portrayed King Henry Plantagenet in "Beckett" and "The Lion in Winter."
As stated, Lady Salisbury is condemned because she 'has Plantagenet blood'. However, every British monarch since Edward V (R. April 9, 1483 - June 25, 1983) decends from the Plantagenets
Jake Maskell and Max Brown who play Henry Pole and Edward Seymour in this episode go on to both be in another show about royalty The Royals. Jake Maskell plays Max Brown's uncle in The Royals.