This quirky rose is also known as the Crested Moss or rosa centifolia cristata; it was apparently discovered in the 1820s growing against a convent wall in Fribourg, Switzerland.
The fringed, mossy sepals give the buds a shape similar to Napoleon’s hat, hence the name, and people are always intrigued the first time they see them. It is hardy in Zones 5 to 7 and should be fine in Zone 4 with a little protection.
The scent is exquisite but the foliage up the long arching canes is a little sparse; in my garden I peg some of them down into the soil amongst neighbouring plants and new laterals form along their length so you end up with rose flowers over a large area.
lynnerevettebutler 
My daughter gave me this rose a few years ago. The scent is heavenly and it is impossible to resist stroking the mossy bits. I’m going to try pegging them down as you suggest. Your photos are gorgeous.
Glad you enjoyed the photos and that I’m not the only adult who strokes the mossy buds on this rose! I hope the pegging method works for you too, perhaps you could post another comment here one day to let me know the result.
Beautiful – I would love to try this rose, but I don’t have any free space in the garden!
I know how you feel; I still have enough space for a few more shrub roses but, as I am now in my mid-sixties, I am trying to curtail my plant purchasing because it is already taking me much longer to care for my existing plants than it did a few years ago. I try to visit a selection of local open gardens each summer which inevitably leads to me writing a list of roses I covet as I walk round! Do you have a particular favourite amongst the varieties in your garden?