First, let it be said that this is by no means a definite list, nor is it complete or necessarily of perfect accuracy. This is a rough draft of what I've noted from collecting these saddles myself, and should be used as a general guide, nothing more. Keep in mind that some '50s-era Brooks lightweight saddles were sold badgeless.

The earliest badge I've seen is shown below - it dates from the 1920s or thereabouts. Unlike later badges, this example appears die cut. Please note that the saddle top has been replaced on this example.

Photo courtesy member Otis from Bikeforums.net

The 1930s badge shown here is presumably the first to have a solid badge design.

Supposedly, the badge shown above was either superceded, or ran concurrently with the following badge in the 1940's, which removed the exaggerated serifs from the font. This particular badge existed into the early 1950's. Examples have been positively ID'ed as late as 1951 (though it doesn't exclude the possibility that this badge was produced later then '51).

Photo courtesy member RHM from Bikeforums.net

I am not sure where the following mid-1940's era badge fits into the mix; it is original to a 1947 Ganna. I presume it may have been used exclusively on Brooks' narrower racing saddles, running concurrently with the earlier two badges prior. Alternately, the design does seem to bridge the gap between the '30s badge and the '40s badge above - it may have been an interim design.

Photo courtesy Franco Spernicelli of Spernicelli Biciclette

By the mid-1950's, the badge was redesigned with a stepped shape to accomodate "Made In England" stamped below the Brooks lettering. These badges are stamped deeper and are of a generally thick metal - they don't dent that easily:

Badge shown in photo comes from unknown-date saddle. Brooks saddles were not stamped with date codes until 1959.

The 1950's design was revised into the brass version shown below, probably in the late '50s (and remaining into the early 1960's). The stylistic redesign remained in use until the 1970's, but was subsequently produced produced in plastic and metal (chromed tin?) as opposed to brass. Plastic versions were generally fitted on the lower-end leather saddles (off and on - I've seen one on a B.15), and almost always on the Brooks vinyl mattress saddles. The plastic badges, riveted to the pliable vinyl, were known for snapping at the rivet hole at one end (to ultimately swing on the remaing rivet until breaking off completely).

Metal badges have been seen as early as 1965. The year of introduction for the plastic or brass variants is unknown. The plastic and metal badges have noticably larger rivets in comparison to the brass examples - these larger rivets remain the norm on Brooks badges today.

Brass variant shown below has no date code; B.66.
Plastic variant stamped with 1979 date code; B.73.
Metal variant date code unknown; B.72.

Brass	Plastic:	Metal

Do note that Brooks' higher-end racing saddles (most notably, the Professional) of this era utilized a completely different badge of which two variants exist. One is stepped, with narrower ends; the other is shaped in the typical rectangle with curved ends. Apparently, these badges are prone to the letters wearing off. v2 was used between 1973 and 1979 at the least.

v1 shown below is presumed to be a 1973 small-rivet Pro
v2 has been seen on Brooks Pros as early as 1973 and as late as 1979, both large and small rivet.

v1	v2

Photos courtesy member Gearbasher from Bikeforums.net

When Sturmey-Archer aquired Brooks, a badge was developed based on the revised Sturmey-Archer font. These date from the mid-late '80s (if not later), and are the smallest Brooks badges that I know of. This design - to my knowledge - spanned all models, from B.72 to Pro:

Saddle shown in photo is undated, Brooks Professional Pre-Softened.

The last retired badge design - used around the mid 1990s - were uninspired modifications of the Helvetica font with "England" marked below. Copper rivets were used:

Saddle shown in photo is undated, Brooks Professional Pre-Softened.

NOS 1990's badge & rivets generously donated by Wallingford Bicycle Parts

Current badges can be seen on present production saddles, and resemble the 1930's badge with lettering similar to the badges of the '60s and '70s. The copper rivets of the generation before were dropped in favor of chromed steel rivets.

NOS current badge & rivets generously donated by Wallingford Bicycle Parts
Saddle photo courtesy member Gearbasher from Bikeforums.net