The documentation for this type of gown comes from various Italian, mostly Tuscan paintings or frescoes from the late 13th and early 14th century. I have written a little about this type of gown in two blogposts, where you can see many more images. Post 1. Post 2.
Anyway, this gown is constructed with a waist seam over the bust, as can be seen for example on this fresco:
It is obvious from the painting above that neither the bodice seam, nor the tie should go under the breasts, but across them. That painting is from the cathedral of San Zeno in Verona, and so is the image below too, which I used as my primary inspiration: The trim is taken from this gown and so is the slit in the skirt part, all the way up to the "waist" seam. This one appears to be worn without the ribbon belt.
Here are some other Italian images from the early 14th century, showing the high "waists" and also slits in the overgowns.
The seam above or across the bust really seems weird and contra-intuitive to us, but it is not unknown in the history of costume. One of the oldest Swedish folk costumes, Vingåkersdräkten, is made in this way:
This gown is of course not documented before the 18th century, and has no connection to Italy. But that it existed at least made me more confident about cutting my fabric.
Incidentally this folk costume is also often described as "medieval in style" in older books about folk costumes. To this I usually respond - bah! There are no medieval gowns either depicted or preserved from Northern Europe with this construction. But maybe the Swedish scholars writing 70 years ago or so had seen images of these Italian gothic frescoes, and not knowing much about medieval dress at all, thought that this was a typical medieval dress for all of Europe. With their ideological bias which prescribed ancient roots to the clothes of the peasants, they were ready to track almost anything to the Middle Ages given half a chance anyway.
My gown is hand sewn from a very thin teal and black shot silk, and lined with a printed cotton. The hem is bound with a grosgrain ribbon to protect the silk and very thin cotton. The gown is trimmed around the neck, sleeves, armscyes and down the front of the "bodice" with a metal ribbon woven at a factory museum in Gothenburg, where I live.
Cotton fabric was imported to Italy in the 13th century; usually very fine cottons with printed patterns, from India or the Islamic world. But they were also woven in Italy in the 13th and 14th centuries. The fabric made locally was usually either in a solid colour or with woven patterns and usually heavier. Mostly they were half-cottons, with linen warp (fustian).
My lining fabric is of the type that would have been imported from India, and while not a perfect copy of period printed fabrics the scroll-like pattern at least resembles medieval Indian cottons somewhat.
Blurry photo of lining:
13th - 14th century, found in Fustat, Egypt. From the Metropolitan Museum of Art
Of course we cannot assume that these cotton prints, which were exported from India to Fustat in Egypt were similar to those preferred in Italy at the time - in fact we do know that the Indian traders and printers varied their prodcuts according to local, and changing fashions. So I had to settle for "reasonable". As you can see mine is done by reserve printing, unlike the red fabric above. There are, hwover, contemporary prints with reserve technique too:
Also the Met.
I have lots of images of early printed textiles on a Pinterest board.
I chose blue both for aesthetic reasons and because dyeing with indigo was very popular in India both in the Middle Ages and later.
Fur, or another silk would have been a more easily documentable choice, but I'm using stuff I already had. And it does make for a both warm and still extremely lightweight gown.
I awas also inspired by this slightly later fresco by Bernardo Daddi, showing cloaks with what appears to be linings with an either woven or printed pattern.