J.R.R. Tolkien: Artiste et illustrateur

His artwork seems so distinct and expressive—I'm curious what sources or ideas fueled his artistic choices and how they influenced his storytelling.

Seeing his sketches and paintings adds a new dimension to Middle-earth for me. Has anyone else felt that the illustrations deepen their understanding of the books?

His sketches feel so detailed and intentional, but I wonder if there was a lot of organic growth or if he had a clear plan from the start.