J.R.R. Tolkien (1892–1973) was highly influential in shaping modern fantasy literature and popularising medievalism. Scholarship has examined various aspects of Tolkien's literary imagination in The Lord of the Rings (1954–1955); however, to date, there has been no thorough scrutiny of the significance of aesthetics in his creative works. This paper contends that Tolkien's magnum opus as part of his long‐life myth‐making project was shaped profoundly by the late 18th‐century aesthetics of the sublime. It draws on Burkean physiological sublime to argue that contrary to Kantian rationality, certain Tolkienian landscapes demonstrate the qualities of the natural sublime and generate physical experiences on the observer that accentuates the primacy of emotions over reason. The article proposes a new direction in Tolkien studies by highlighting the aesthetic overtones of Tolkien's engagement with the sublime, which played a significant role in constructing his English mythology.