It includes a couple of surprises.
"In the meantime (from 1900 onwards) a new type of beer in the form of sugar-sweetened and pasteurized Malzbier (Karamelbier) had appeared, giving top fermentation a considerable boost, which has also recently involved the top-fermented, light bitter Lagerbier which was already brewed in the Rhineland.
Otherwise, the old local beers are mostly forgotten. Even famous beers. Such as Danziger Jopenbier, Einbecker beer. The widely spread Porter. Münsterländer Altbier, of which only remnants of inferior quality remain.
A few have managed to survive into the present day, such as Broihan (Hannover)*, which is brewed using wheat malt and has a sweet taste; the dark and weakly sweet brown beer brewed in the Kretschmerei in Breslau, Hamburger "Beer", Lichtenhainer beer and Gose, the wheat malt beer of Bavaria, especially the Berliner Weissbier, and to a lesser extent the non-sour Weissbier of northern Germany. Grätzer beer has saved itself - as a miserable leftover. Rhenish top fermentation, however, has survived the times in improved condition.
* Brown beer with a schnapps (caraway) has been a well-known popular drink in Hamburg as in Hanover under the name "Lüttge Lage"."
"Obergärige Biere und ihre Herstellung" by Dr. Franz Schönfeld, 2nd edition, Verlag von Paul Parey, Berlin, 1938, page 132.
I'd assumed that Broyhan dies out a decade or two earlier. But, no, it was still limping on in the 1930s.
Lüttge Lage is a weird survivor. It's a type of low ABV Altbier which is still produced in Hanover.
Schönfeld finishes this section with a quick look at top-fermentation elsewhere in Europe:
"In other countries too, top fermentation was pushed away more and more. However, there are still a number of breweries in Holland and France which produce light LAgerbier in a top-fermenting manner to a not inconsiderable extent. In Belgium, top fermentation still remains in the production of old sour beers.Of course, there was far more than sour brown beers being top-fermented in Belgium before WW II. And there was bottom-fermenting beer produced in the UK. Just not very much of it.
A very special exception is England. Only top fermentation is known here. Hundreds of years ago, English beers had a well-founded reputation. They were all strong beers with great durability and characteristic taste and fragrance. They have remained so to this day. Bottom fermentation was unable to gain a foothold. National characteristics and habits have allowed the old method of preparation to hold on."
"Obergärige Biere und ihre Herstellung" by Dr. Franz Schönfeld, 2nd edition, Verlag von Paul Parey, Berlin, 1938, pages 132 - 133.