O Christmas cookies!

At 33d and Arch one afternoon last week, in the sixth-floor precincts of Drexel University's student-run Academic Bistro (can someone please hotten up that name?), the platters of Christmas cookies - chocolate stars and pliable brittles and blond men redolent of ginger - reposed patiently, awaiting their audience.

They were the standard fare circa 1804 and 1824 (moshey, the nut-brittle, and apee cake, baked on a bed of anise seed). And in the case of the crisp snowflake sand tarts (baked like the others by Drexel's culinary students), some still standard today.

In the room beyond, Don Yoder, the silver-haired emeritus professor of folklife studies at the University of Pennsylvania, was holding forth not simply on the evolution of holiday baking in the Pennsylvania Dutch region and counties to the north, south and west, but also on the curious (in Pittsburgh, holiday fireworks were the custom) and unsung evolution of Christmas itself.

If the holiday has been secularized and commercialized and decidedly nationalized, it was not always thus in the microclimates that stretch out from Philadelphia to Lancaster, York, and beyond. In the 1700s and for another century, he said, you can parse a distinctively anti-Christmas faction (at times involving the bulk of Pennsylvanians, sober Quakers, Scotch-Irish Presbyterians, Baptists, once-stricter Methodists, Mennonites, and Amish).

For them, Christmas often was - as Rocky said about Thanksgiving - just another day. In fact Quakers, finding no basis in nature for it (as they found in New Year's Day) and the papal undertone in the name, referred to it as "the day called Christmas."

In the late 1800s, Quakers kept their businesses open on Dec. 25.

Less Puritan in spirit was the pro-Christmas faction, generally the celebratory Lutherans, the Reformed and Moravians - their passion enduring in Bethlehem, Pa. - the Episcopalians, and scarce Catholics.

The occasion of Yoder's remarks was the 50th-anniversary reissue of the late Alfred L. Shoemaker's handsomely illustrated folk-cultural study Christmas in Pennsylvania (Stackpole Books, 2009, $24.95 at www.stackpolebooks.com), for which Yoder wrote the original introduction.

William Woys Weaver, the Devon-based food historian and Yoder's friend, contributed the cookie recipes, part of his campaign - which we'll get to another day - to explore and publicize the homespun foodways of the Keystone State.

The book is a complex and nuanced account - of the now-faded tradition of Belsnickels (roaming posses of bad Santas who would dress in rough clothes and take swipes with a switch at little children), and the popular transformation of the gift-bringing Christ child (in Pennsylvania Dutch dialect the Grisht-kindel) to Kriss Kringle (part of the secular trinity that came to include Santa Claus and St. Nicholas).

In Dutch, which is to say German, Pennsylvania, though, there was nothing subtle or nuanced about what Yoder calls the "orgy" of cookie-baking. By early December, cookie cutters emerged from the attic, and the women of the house baked cookies "by the washbasket-full."

Why such profusion? "You needed many . . . to appease the appetite of 40 or 50 Belsnickels who came-a-begging Christmas Eve," and for the widow down the road, and dozens to trim the tree, and to display in the window facing the lane, and dozens more for the lady from across the valley who'd lent a couple of animals that a mother didn't happen to have among her own extensive cookie-cutter flock - "a deer, or an exotic elephant, perhaps."

And of course because, as they did the moment Yoder's talk ended in the Academic Bistro, they tend to disappear quickly; in the wink, you might say, of an eye.