Lisa Grimm traces the origins of the seasonal brew:

Before it was deemed a health tonic, pumpkin beer was a popular component in cups of flip—something akin to a cocktail that typically mixed rum, beer, and sugar. Pumpkin beer and brown sugar were more easily found in early America than their all-malt and refined counterparts, so they became part of the go-to recipe. But the main reason pumpkin was adopted as a beer ingredient during the early colonial period was simple availability—pumpkins were a native plant (one completely unknown to most Europeans before the 16th century), while good malt was not so readily accessible—fermentable sugars had to be found where they could, and in the first pumpkin beers, the meat of the pumpkin took the place of malt entirely.

Erik Loomis looks at how pumpkin beer is perceived by today's foodies.

(Photo of "Tom Waits pumpkin" by Flickr user abbyladybug.)