The The Hobbit in popularity.
The themes of the Lord of the Rings have been extensively studied. To understand them you have to take into account J. R. R. Tolkien's influences. Earlier in life, he had fought in some of the fiercest battles of World War I, and witnessed the monstrous machinations of war. During World War II, Tolkien wrote the trilogy, drawing much inspiration from the faceless evil that threatened his homeland and family. War and peace, good and evil, are obvious themes for his work, but there are more underlying influences. Tolkien witnessed, as a child, the lasting effects of the industrial revolution. Wide open countrysides and quaint villages were transformed into dark and drab industrial wastelands. This theme is an undercurrent throughout the trilogy; many of the darkened, sundered settings portrayed in the books could have been picked out of the landscape of industrial England. The Shire is much like the countryside of Lancashire and Mordor resembles Black Country, home to most of industrialized England's coal mines.
Any way you look at it, The Lord of the Rings is an epic story enjoyed by adults and children alike.
