Apparently the plant grew in Númenor and was brought to Middle-earth by Númenóreans during the Second Age. Among the Dúnedain it was known as sweet galenas, and in Gondor it grew as a wild herb, appreciated primarily for its fragrant blossoms. Among the Gondorians it was known popularly as westmansweed, a reference to its origin.
It was not until the Third Age, when the Hobbits (possibly those in Bree) were the first to use it for smoking. From Bree the habit of smoking pipe-weed spread to other regions, as well as to other races, such as Men, Dwarves and Wizards. In the Shire it was first domesticated, despite its foreign origins, by Tobold Hornblower of Longbottom in Southfarthing around S.R. 1070. 
The cultivation and exportation of this herb became a key industry in the Shire, especially in the south. Popular varieties of pipe-weed included Longbottom Leaf, Old Toby, and Southern Star from the Shire. Perhaps less popular was Southlinch from Bree.
The Wizard Gandalf learned to smoke pipe-weed from the Hobbits and was often seen blowing smoke-rings. Saruman initially derided him for this, but at some point he took up smoking himself. and even had commerce with the Shire: After the destruction of Isengard, pipe-weed was found among its stores, but the Hobbits Merry and Pippin failed to realize the sinister implications.
The common Gondorian name of pipe-weed was Westmansweed. The more noble name was galenas (a Gondor Sindarin form of of the proper Sindarin form galanes), meaning "pipeweed" (or "sweet smelling growth"[source?]).
Portrayal in adaptations
2007: The Lord of the Rings Online:
- The smoke from Sweet Galenas takes the form of a sailing ship that floats out from the pipe.
- ↑ 1.0 1.1 J.R.R. Tolkien, The Lord of the Rings, The Return of the King, "The Houses of Healing"
- ↑ 2.0 2.1 2.2 2.3 2.4 J.R.R. Tolkien, The Lord of the Rings, "Prologue", "Concerning Pipe-weed"
- ↑ J.R.R. Tolkien, The Lord of the Rings, The Return of the King, "Homeward Bound"
- ↑ J.R.R. Tolkien, The Lord of the Rings, The Return of the King, "The Houses of Healing"
- ↑ J.R.R. Tolkien, "Words, Phrases and Passages in Various Tongues in The Lord of the Rings", in Parma Eldalamberon XVII (edited by Christopher Gilson), p. 100