Fit to Rule: How Royal Illness Changed History

In the final episode, Dr Lucy Worsley investigates the medical histories and fraught family dynamics of Queen Victoria and her descendants. She begins and ends with two events which challenged the very survival of the crown and revealed how crucial the physical and mental health of the royal family remained: the sudden death of Princess Charlotte in 1817, and the abdication of Edward VIII over a century later.

In 1817, 21-year-old Princess Charlotte was the Hanoverian dynasty's great hope: popular with the public and about to give birth to her first child, thereby securing the royal succession for another generation. But, after a 50-hour labour, recorded in minute-by-minute detail by the country's leading midwife, the baby boy was delivered stillborn, and hours later, Charlotte died too. The nation was shocked by the sudden loss of the monarchy's next two generations, and a frantic race ensued for King George's unmarried sons to be the first to produce a legitimate heir. Two years later, the Duke of Kent's new German wife gave birth to a daughter, Princess Victoria.

Whilst producing children was not a problem for Victoria, rearing an heir who was fit to rule was another matter. Fearing their eight-year-old son and successor, Bertie (the future Edward VII), was not psychologically up to the job of king, Prince Albert turned to the new pseudo-science of phrenology in a bid to get to the root of his son's problems, and Lucy charts the effect their difficult mother-son relationship had on both their reigns.

Lucy also reveals the emotional strains the royals faced as they tried to reconcile the competing demands of public duty and a private life. She examines how Queen Victoria's severe depression after Prince Albert's death almost cost her the crown, and explores the emotional turmoil of Edward VIII, who ultimately declared himself unfit to rule, choosing love over the throne.