Keen Robinson and Co
Manufacturers of Keen's Mustard
1742 Keen's Mustard first made by Keen and Sons.
1864 Agents for Oswego prepared Corn.
1935 Creation of barley water for the Wimbledon tennis championship - a Colman's representative created a drink to refresh and hydrate the players, by combining barley crystals with lemon juice, sugar and water.
1992 a special 250th anniversary tin of Keen's Mustard, sold in Canada, contained the following: For over 250 years, Keen's has provided premium quality Dry Mustard to discerning customers around the world. The brand was first manufactured and sold in 1742 by Messers Keen and Sons in the Garlick Hill section of London, England. Keen's quickly established itself as a superior mustard, winning prestigious medals in London, Paris, Moscow, Australia and Philadelphia while also obtaining royal warrants to William IV, Queen Victoria and Napoleon III. Today the tradition continues. Keen's Dry Mustard is manufactured by Colman's of Norwich by appointment to Queen Elizabeth II, and remains the "genuine double superfine" grade. Insist on the very best. Use Keen's Dry Mustard. Imported by Reckitt and Colman Canada Inc. Toronto Ontario M8Z 5M5
1998 McCormick took over the Keen's brand in Canada and Australia. Although historically a maker of dry mustard, since 1963 Keen's has also been available in Canada as a prepared mustard.
2008 Keen's Mustard is now less known, in the UK, than the Robinson's Barley Water drink.
- The expression "keen as mustard", often thought to have originated with the mustard by Keen and Sons, actually predates it, since the Oxford English Dictionary cites examples of the use of the expression from 1672.
Sources of Information
- Robinsons website 
- Advert 1864 A.
-  Wikipedia
- Trademarked. A History of Well-Known Brands - from Aertex to Wright's Coal Tar by David Newton. Pub: Sutton Publishing 2008 ISBN 978-0-7509-4590-5