The traditional amber Bavarian lager historically brewed in March (März) and lagered through summer for fall consumption. Rich toasted Munich malt dominates, with a clean lager profile and moderate bitterness. Typically 5.6–6.3% ABV. Served at Oktoberfest until the late 20th century, when Festbier (paler, lighter) largely displaced it on the Wiesn — though Märzen remains the style most Americans think of as ‘Oktoberfest beer’.
In the glass
Origin
Märzenbier (“March beer”) originated in a 1553 decree by Bavarian ruler Duke Albrecht V that forbade all brewing between April 23 and September 29 — a public-health measure intended to avoid the warm-weather bacterial spoilage that routinely ruined pre-refrigeration summer beers. Bavarian brewers responded by brewing stronger, more heavily-hopped beer in March and lagering it through the summer for consumption in early autumn. The style was codified as “märzenbier” in 1841, when the Spaten Brewery of Munich introduced the first officially-labeled märzen at that year’s Oktoberfest; in a parallel development, the Dreher Brewery of Schwechat near Vienna released its similar Vienna lager the same year. In 1872 Spaten brewed a märzen-style beer specifically for that year’s Oktoberfest and labeled it “Oktoberfestbier” — the foundation recipe on which Spaten’s modern Oktoberfestbier is still largely based.
Märzen and Oktoberfestbier were historically much darker (nearly brown) and noticeably stronger than the beers now sold under those names; in recent decades Munich brewers have lightened both color and body as a concession to modern tastes. North American craft brewers often brew closer to the older, darker template than contemporary German producers do.
Notes
In Germany, “Oktoberfestbier” is a legally reserved term — only the six Munich breweries permitted to serve at the festival itself (Augustiner, Hacker-Pschorr, Hofbräuhaus, Löwenbräu, Paulaner, and Spaten) are allowed to use it. Every other German brewery calls its version “märzen.” Outside Germany the two names are used interchangeably with no legal weight — the American Oktoberfests you see each fall are, by German rules, märzens.
Märzen is a close cousin of Vienna lager, and the two overlap considerably. The usual rule of thumb: märzen leans on Munich malt (deeper gold to amber, toasty-bready), Vienna lager on Vienna malt (lighter, a little more reddish, slightly drier). In practice international brewers don’t always honor the distinction.
Defining examples
Paulaner Oktoberfest-Märzen·Ayinger Oktober Fest-Märzen·Hacker-Pschorr Original Oktoberfest·Great Lakes Oktoberfest·Sierra Nevada Oktoberfest