They hugely political and have strong religious influences. The books are indeed about the industrial revolution, coal mining, WWI, oppression, the landscapes of England and his best friend was CS lewis wrote fantasy (Narnia) as well, but also wrote innumerous theological works. They met at a pub every week and talked about their writings. He was a brilliant cartographer (maps) and linguist (Elvish,etc). The languages and customs of the creatures in his books come from the rich history of England itself and lost languages, songs, poetry and customs. There is some great specials on his life on those discs if you watch them. He was truly brilliant.