A mini rose window?

I saw the most fascinating thing yesterday. I had been in that building many times, and in those two rooms, but never noticed this little circular window on the kitchen door.

Who put the window there, and why? I don't think it had a practical purpose, because the glass art warps what you see on the other side. The symbol looks like a sort of fleur-de-lis. I love that this little window is there. I can't imagine any reason of its being there other than beauty.

The light going through this little rose window was spectacular. Has anyone seen anything similar? What can you tell me about this little cicular window? For the record, this is a house in Sweden.

Thank you for stopping by Pieliekamais!