On a recent evening inside the Hotel de la Poste, an alpine hotel in Cortina d’Ampezzo, Italy’s most ski-and-be-seen winter destination, a boisterous party celebrated the birth of a cinematic era.

Forty years earlier, the libidinous, up-chalet down-chalet comedy “Christmas Holiday,” set in the lodge, was released. Nominally about a plain but lucky-in-adultery piano bar singer and the wealthy Milanese, salt-of-the-earth Romans and tuxedoed bons vivants who surround him, the film previewed decades of gleefully vulgar, broad and formulaic Christmas comedies that earned a fortune and came to be known, after the cakes Italians devour during the season, as “Cinema Panettone.”

To celebrate the anniversary, the film’s producer, writer and stars carved up an enormous panettone the size of a fire hydrant and participated in a weekend of cinepanettone-themed festivities.

Revelers in fur, sequins and ski sweaters reading “Cortina” or “Mountains and Champagne” danced to “Dance All Nite,” “Maracaibo” and other Italian ’80s classics on the movie’s soundtrack. They sang along with the film’s protagonist at a raucous dinner cabaret performance. They hit the slopes and raced down a slalom, trying to finish a slice of panettone before reaching the finish line.