Tolkien, WWI, and The Ring

From the BBC, an examination of how J.R.R. Tolkien's World War I experience influenced The Lord of the Rings, including this focus on Frodo's "shell-shock" back home in the Shire:

Shell-shock was prevalent among men on both sides of No Man’s Land, and by the end of the conflict around 80,000 British soldiers had been treated for the condition. Symptoms included vivid hallucinations and nightmares reliving traumatic events, anxiety and depression, emotional numbing and changes in personality.

Tolkien would have been well aware of its effects from his time in hospital and on the front line. He presents a sympathetic view in The Lord of the Rings by afflicting Frodo with the condition while carrying and after having destroyed the Ring.
 

Even before reaching Mordor, Frodo experiences sudden temporary blindness on a few occasions, a common symptom of shell-shock, and as he gets nearer to Mount Doom he experiences a loss of taste and smell, uncontrollable trembling, exhaustion and bouts of anxiety.

Pacifism and withdrawal

Upon his return to the Shire, a change in Frodo's personality becomes increasingly evident. The Shire is overrun with thugs and hooligans, and while Merry and Pippin call the hobbits to arms, Frodo refuses to take part and insists that no-one be hurt or killed.
 

Shell-shocked soldiers, including the poet Siegfried Sassoon, often became pacifists after the war. Many also began to lose interest in things they had once found enjoyable, and isolated themselves from society as a way of protecting themselves from reminders of their traumatic experiences.
 

While Merry, Pippin and Sam reintegrate successfully back into Shire life, Frodo quietly withdraws and is plagued by terrifying flashbacks and nightmares.

John Rhys-Davies, who portrayed Gimli the irascible dwarf in Peter Jackson's The Lord of the Rings trilogy, presents the series. More about Tolkien and WWI in this book.