The Tolkien Ensemble take on the same song:
What manner of creature or being Old Man Willow is exactly is not made clear in the book. It is possible that he may be some form of Ent, or more likely a Huorn, the latter being a more wild and tree-like Ent. Unlike the Ents that appear later in the book, Old Man Willow does not appear to be able to walk, but draws his victims to him instead (though it is suggested that some of the trees in the Old Forest do move). Later, Treebeard explains that Huorns tend to be angry and vengeful, a description that fits Old Man Willow well.
The Ents and Huorns were probably influenced by the sentient trees of many real-world mythologies. These include talking trees that might tell the future, or help a person look for Leprechaun gold. Alexander the Great and Marco Polo were both said to have visited a prophesying Indian tree. Oak and Rowan trees might be conversed with by Druids. In Greek mythology, spirits called Dryads were said to inhabit trees, with which they shared a deep connection; a dryad would often die if their tree was cut down. Tree spirits are common in other cultures too, such as the Japanese kodama. Trees, magical or not, are sacred in many different cultures.
Talking, walking, and magical trees can be found in many other fictional works, as can dryads and tree spirits. Talking, dancing trees and their tree spirits appear in the Narnia books, written by Tolkien’s friend C. S. Lewis. Dryads are also mentioned in Milton’s Paradise Lost. In The Wonderful Wizard of Oz, The Forest of Fighting Trees attacks the Scarecrow. Kodama appear in the animated film Princess Mononoke.
Water spirits or goddesses can be found in numerous mythologies around the world. They are usually the protector of their own particular spring, river, or body of water. Depending on the mythology they can be shy and secretive, or very dangerous, and are almost always captivating and seductive. In Japanese folklore, a Kappa is a type of water sprite, and in ancient Greek mythology Naiads are nymphs attached to rivers, springs, fountains and wells. The Neck, or Nixie, is a Germanic and English water spirit that loves music and will lure humans deep into their waters to drown. A similar creature is the Slavic Rusalka. In Wales, water spirits called Morgens will drown men, and in Scotland the Kelpie might lure children to their death. The Scandinavian Huldra might be kind to those who show her respect, but can also be ruthless and severe. Most water spirits take the form of beautiful young women with long flowing hair, and many, such as the Kelpie and Nixie, can shapeshift into other forms.
If Goldberry is a river spirit, then she seems to be of the benevolent kind, and possesses additional powers that allow her to control the weather (Tom mentions that it is raining outside because it’s Goldberry’s ‘washing day’).
The belief that spirits inhabit animals, plants and natural features is called animism, and is important to many religions and cultures, such as Shinto and Shamanism. Nature worship in general can be found all over the world.
A mound of earth and stones covering a grave in this way is called a tumulus, barrow, burial mound, or kurgan. These forms of burial can be found in a number of cultures, including ancient Greek and Norse societies, and are usually reserved for kings or important people. They can also be seen in Britain, constructed in the Bronze Age, and later by the Vikings and Saxons. Burial mounds might include one or more inner chambers for the burial of the king and his family, along with his gold and prize possessions. The latter might include weapons, armour, and even horses. In some cases the inclusion of these items could be based on a belief that the dead were able to take possessions with them into the afterlife.
The barrow-wights are based on draugar, Norse ghosts who inhabit Viking graves and guard the treasures buried there. Draugar are incredibly strong and possess magical abilities, such as the power to shapeshift and control the weather. Their presence can also drive a mortal insane. When they have killed their victims they will often eat them or drink their blood. They can be harmed by iron, but it takes a hero to properly vanquish them, as told in Norse folklore. Stories such as Hervararkviða, an Old Norse poem from the Hervarar Saga in which the shieldmaiden Hervor visits a barrow ghost to reclaim a family sword, may have influenced Tolkien when creating his barrow-wights.
There has been a great amount of debate amongst Tolkien fans concerning what kind of being Tom Bombadil is meant to be. The character does not seem to easily fit into the various orders of beings that Tolkien established. Tolkien himself stated "even in a mythical Age there must be some enigmas, as there always are. Tom Bombadil is one".
However, this has not prevented fans from speculating. Here are some possible explanations:
Tom Bombadil is Ilúvatar (God). This is reinforced by Goldberry’s statement: ‘He is’, calling to mind the response of God when Moses asked his name: ‘I Am that I Am.’ (Exodus 3:14) However, comments made at the Council of Elrond and elsewhere seem to suggest that Bombadil is not as powerful as Sauron, and Tom himself says that his powers do not stretch east of his land. In his letters, Tolkien wrote that “The One [Ilúvatar] does not physically inhabit any part of Ea [the created universe].”
Tom Bombadil is a nature spirit. This would explain his love for his land, and his matrimony with Goldberry, who appears to be some form of water spirit (see bookmark for page 141). He does not seem to be tied to any particular natural feature, so might be taken as a spirit of the land itself – of Middle-earth, or even Arda. This would fit with the titles ‘Eldest’, ‘Master’ and ‘Last’. The ‘Bombadil as nature spirit’ theory is backed up by Galdor at the Council of Elrond: “Power to defy our Enemy is not in him, unless such power is in the earth itself.”
What is Tom Bombadil? - a discussion of Tom Bombadil, and a persuasive argument for him being a nature spirit of Arda.
One more hint as to the true nature of Tom Bombadil was revealed in an early letter from Tolkien to his publisher: “Do you think Tom Bombadil, the spirit of the (vanishing) Oxford and Berkshire countryside, could be made into the hero of a story?” Tolkien was extremely disturbed by the increasing industrialisation, spreading cities and vanishing countryside of England, a theme that will be picked up later in Lord of the Rings.