It all started innocently enough. Back in the mid-1970s, Rita Breuer began collecting old German Christmas ornaments after her husband expressed the desire for a good old-fashioned Christmas tree like his grandmother used to have. Breuer, who hails from the small town of Olpe, 60 kilometers from Cologne, scoured flea markets and raided friends' attics in the search for baubles and came to accumulate quite a collection which included not only tree ornaments, but also Advent calendars, cribs and Christmas cards.

But then something strange happened. Breuer, who was now being helped in her quest by her daughter Judith, came across more and more objects that didn't fit with the usual peaceful image of Christmas, lsuch as World War I-era miniature soldiers, bombs and hand grenades designed to hang on the tree. The Breuers started to get interested in how Christmas had been abused for propaganda purposes over the years, most blatantly by the Nazis. Their hobby turned into a full-fledged amateur research project.

Now, more than 30 years after Rita Breuer first began collecting Christmas knickknacks, selected objects from the family collection have gone on show at the National Socialism Documentation Center in Cologne. The exhibition, which looks at the history of Christmas and propaganda from the 19th century until the present day, focuses on how the Nazis misused Christmas for their own foul purposes and tried to turn it into a "Germanic" winter solstice festival.