Beaumont Marjoribanks (1742-1845) is largely credited with the discovery of Gillyweed and its effects. A noted pioneer in Herbology, he dedicated his life to the discovery, collection, and classification of many rare magical plants, until he died at the ripe old age of 103.

There is some dissent among historians surrounding Marjoribanks for a few different reasons. The first, and most famous, is the controversy over his "discovery" of Gillyweed. After Marjoribanks announced his findings and forevermore carved out a place for himself in the ranks of the great witches and wizards of our time, some startling evidence came to light. 

The re-investigation of some obscure texts which had been tucked away in a private library for decades revealed that someone else had actually discovered the properties of Gillyweed almost an entire century earlier. Elladora Ketteridge, a little-known witch had risked life and limb in the early 1700s investigating the until-then mysterious properties of Gillyweed. After eating the plant she nearly suffocated, but managed to save herself by sticking her head into a bucket of water nearby. After recovery, she documented her discoveries about Gillyweed in a treatise, which was almost entirely overlooked. As a result, she was never credited with this discovery. Whether Marjoribanks claimed ownership of this finding either ignorant of or willfully ignoring information about Ketteridge is unknown.

The second and, in my opinion, much less serious controversy about Marjoribanks is the spelling of his last name. While in Britain and in most of Europe you will see his name as it appears here, it is spelled quite differently by our peers across the Atlantic. In America, his name is spelled "Majorbanks" - and they are extremely sensitive over this spelling. It has not been uncommon for duels to occur between British and American herbologists over the spelling of Marjoribanks' name in a dissertation on semi-aquatic plants.