The fourth most common ingredient in historical mead recipes is rosemary. It is the most common herb, and is more than 50% more common than the next herb on the list.
Rosemary is used as the only flavor addition in only 2 of the over 500 recipes it appears in.
Its prevalence appears to increase over time, being less common in meads from before the mid-17th century than in those dating after that time.
Rosemary from Fuch’s Herbal
For spices rosemary is most commonly paired with ginger, at a frequency that appears to be higher than expected based on how common ginger is. Rosemary is a common partner to citrus (a lemon-rosemary mead from the mid-17th century has been a very successful recipe for me). When used with other herbs, marjoram, sweet briar, and thyme are its most frequent partners.
Rosmarinus officinalis, has been used as a name for rosemary for hundreds of years, and is by far the most common member of the 5-species genus. Proving that changes in plant names are not purely a historical phenomenon, in 2017 Rosmarinus officinalis, was officially re-assigned to the much larger larger Salvia genus as Salvia rosmarinus. This decision was made based on DNA analysis. Because Salvia is so large a group, some plant taxonomists believe it should be broken up, other argue the DNA evidence argues otherwise. Maybe they will have some productive debates over a mazer of mead containing rosemary?
Rosemary does come in a wide variety of cultivars, but the differences in flavor between them is generally noted as being subtle rather than notable. Choice of cultivars appear to be more commonly made for aesthetic or climactic consideration than because of flavor.
Thanks to the Wellcome Collection for the illustration of rosemary from Fuch’s herbal.