One of Orthodox Christmas traditions is koledari - a kind of Christmas caroling. One of Russian names for Christmas eve is коляда, and koledari is called similarly–колядки.
Here are some 19 century postcards depicting koledari.
This blog is about old postcards, book illustration and all kinds of paper whimsy from the Soviet Union. I'm a long time collector, and this blog is 7 years old. I have an etsy shop for cards, books, pins and vintage finds from Russia.