Jensen's gins are named for founder Denmark-born Christian Jensen. His personal experiences with gin led him to favor the style of heavier, more flavorful gins from the earlier part of the 20th century as opposed to the crisper, modern-style gins. The result was the founding of Bermondsey Gin Limited, which is meant to produce precisely the style of gin that Jensen craves and wants to introduce to the market. (From the Taster's Guide) First launched in 2004, we're told that the product has moved away from the Thames Distillery of England and is now producing their own gin at their own Bermondsey Distillery.
Jensen's Bermondsey gin is a one he considers a London Dry but is closer in style to the gin that began the Gin Craze hey-dey of the 1830s and forward. "Bermondsey" is the name of the street on which the gin company is located. It came about from their investigation of older, out-of-production gins and a reproduction of that style. They specifically note "the absence of contemporary botanicals" and a "focus on balance."