The wallpaper is called "Ken Kiuruista Kaunein", translating "who is the fairest of the larks?"
It was designed by Finnish ceramic artist and designer Birger Kaipiainen (1915-1988) in the 1950's.
I had seen bits of it before, online and the test sheets they have of it, and always wondered what the hell was going on there; if you look at just a detail of it it's kind of weird and the birds sort of ugly. Well, yeah. But once I saw a picture of the wallpaper on a wall I was totally smitten by it. It builds up a beautiful pattern.
Well of course, this is really the way it is with all wallpapers, you have to see them at large to really get an idea. Some patterns that look great when seen as a detail in a catalogue may be a disappointment on the wall; personally I don't like it with decorative patterns that although they are made to appear asymmetrical turn "stripy" when put together, for example.
Tapettitehdas and you can get it from Tapettitalo, where is where we have bought all our wallpapers from. (I'm also assuming that you by now figured out tapetti is Finnish for wallpaper.)
(And btw by now you probably also notice you can fit whole sentences into just two words in Finnish. Or, in fact, one. End of mini-langauge lessons.)
Another little btw, there's an exhibition of Birger Kaipiainen's ceramics at Emma, the Espoo Museum of Modern Art, which is just around the corner from us.