In the US (where the majority of breweries were started by German immigrants, after all), "bock" beer eventually came to mean (some might say "devolved into" ) "...a special brew of heavy beer, usually darker in color and richer in taste than regular lager beer. Bock beer is generally prepared for consumption in the spring, about Easter time." (From the Master Brewers' Assoc. of America's- "The Practical Brewer" 1946).
Arguably, "bock beer" in the US, just slightly darker and *maybe* a bit more alcoholic than a brewer's "regular" beer, was the most prevalent non-"fizzy yellow light lager" style in the pre-micro days, sold as a seasonal, tho' it was slowly dying out. Genesee, Schmidt's of Phila., Yuengling, Stroh, Augsburger, Leinenkugel, Point and a few others still sold them (usually only in spring) into the 1970's. In Texas, Shiner Bock came to be one of their primary brands, even inspiring Anheuser-Busch to market an imitation.
In some ways, the most "traditional" aspect of US bocks was the frequent use of a goat on the label and advertising POS items. Genesee's was probably the most perplexing- a cute cartoon goat on a lime green background covered with primitively drawn daisies. Perhaps the only beer label that seemed to be designed with the "11 year old female" segment of the market in mind ("Oh, Daddy, how cute! Buy this beer!"). Here's the can version:
The goat, legend goes, is there because the word "bock" is also, in German, the term for a "billygoat". Other theories include an astrological explanation.
This US style of bock is now looked down upon by micro-fans (and they have their point- it could be viewed that "US bocks" are bocks they way Miller Lite is a "fine pilsner beer") but I think the sub-style has it's benefits. The somewhat recent Anchor Bock seems to have been inspired by the US traditions, and it gets poor ratings because it's not a German style bock.
There's a great collection of US bock labels here (click "next" to page thru 'em):
I know at least one oldtime brewer who called these beers 'racking room bocks', as they were merely the regular brew with caramel coloring. (This doesn't necessarily apply to all the old US bocks, of course, but apparently this was far from uncommon.)
I recall even in the late '70s you could get a number of bock beers from major US breweries.
re: Jim Dorsch
I was still seeing (and drinking) them in the early 80's, though I don't recall having one since then (awesome link, btw, JessKidden). Probably an AB product, if I recall. Anyway, here's what Dave Miller had to say about the style in his 1988 book "The Complete Handbook of Home Brewing":
"Finally we come to the runt of the litter, the American "bock" whose only resemblance to the German Original is its dark color. Many of these beers are made simply by adding caramel coloring to ordinary light lager. Such shenanigans are an embarassment to the brewing industry. On the other hand, a few breweries have, on occasion, produced a dark beer which, while of ordinary strength and much lighter in body and flavor than the true German bocks, is nonetheless a worthwhile drink."
One would hope that the Anchor interpretation of the latter version.
That being said, on to abu applesauce- there is lots of great info in this thread already (including LStaff's link), but I just wanted to clarify that Sam Adams' Double Bock is brewed to the German style, not the American one, even though the term "Double Bock" is an Americanization of the word Doppelbock. And it is definitely good, though you should definitely look into Ayinger and Paulaner's take on the style. And Einbecker's Ur-bock and Maibock while you're at it.
re: "Carmel colored lager= US bock".
Yeah, well, I never said that they tasted good <g>.
I don't know- I guess I hope that if some of those breweries held on for a few more years, maybe things would have been different. Certainly, in brewing and in other industries, there have been examples of companies "going backward" and making a product that had been cheapened, good again. Restaurants that went back to hand cut fresh potatoes for fries, soda bottlers that've gone back to sugar in place of HFCS, etc. (It's still happening- A-B brewers apparently talked the marketing guys- who were "re-introducing" the old Michelob hourglass bottle- into changing the beer back to an All-Malt lager.)
You got to wonder WHY those last producers of bocks even bothered- was the expense of different labels, seasonal distribution worth it to those penny-pitching also-rans? I have no doubt that it was easy for some supplier salesman to show up and say, "Oh, you guys are still bothering with a different recipe and different malt purchases for your bock? Most of my customers have switched to this snazzy new product ---------------------- and are saving a lot of money". Isn't there a product called "Porterine", still on the market, that's infamous in this regard?
But, I gotta think that any product that's in part made from burnt sugar (carmel coloring), added in quantity to change the color, is going to have some affect on the taste.
Maybe those mid-sized breweries were too saddled with "cheap beer" reputations (that still live on today in microbrew fandom) to change the market the way craft brewers have- on top of having been too big at the time to take advantage of that still tiny segment of the market- economies of scale, brewing to capacity, etc. Sam Adams success with Pittsburgh (and later regionals), Genesee/High Falls new beers, Matt's Saranac line proves that they can brew something other than "industrial light lager" but also suggests that they can't sell enough of it to stay in business without appealing to the "gateway" segment of the market.