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The cap is made up of two pieces of linen fabric sewn together with interlaced herringbone stitch. 8.5-9 cm is left unseamed at the back, creating a split. The bottom edges are pleated and the cap is edged with an embroidered linen strip that continues on to form the ties. Together, the split and the pleated edges create a "pouch" at the nape of the neck when the cap is worn (Dahl & Sturtewagen, 131-133).
At Historiska Världars forum, a Swedish re-enactment forum, reconstructions of the cap have been discussed over the past few weeks, and since I'm currently making myself a late 13th - early 14th century wardrobe I was inspired to make one myself.
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To make my cap, I first took a measurement from the top of my head to the nape of my neck, i.e. the part of my head the cap would cover. I added 8 cm to the measurement (for the split) and used that as a guide when I cut the curve of the two pieces that make up the cap. I made a cotton mock-up to try out the pattern and promptly discovered that the "pouch" was much too large for my short and very thin hair. The cap sagged and looked pretty sad and deflated unless I used the ties to scrunch it up. And the "scrunched-up" version didn't look much like the images in the Maciejowski Bible. For mock-up no. 2, I only added 2 cm for the split, which resulted in tighter cap with a less pronounced pouch that fit me much better, so I used this pattern for my linen cap.
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The finished cap
The final version still looks a little deflated, but that can be remedied with a couple of fake hairpieces...I made these braids from unspun flax and they can be arranged in a number of ways to boost my flimsy pigtails; as long as I cover them up properly they work really well, and I too can have at least the semblence of proper hair!
It can also be worn with the ears showing, as in most of the images in the Maciejowski Bible:
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The decision to make the split very short naturally makes my cap less like the original, with its 8.5-9-centimetre split, but it certainly looks better on me. It's nice and tight, which makes it practical to wear as a foundation for a veil too.
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References:
Medieval Textiles and Clothing 4 (eds. Netherton, R. & Owen-Crocker, G. R.):
Dahl, C. L. & Sturtewagen, I. 2008. "The Cap of St. Birgitta", 99-129.
Dahl, C. L. & Sturtewagen, I. 2008. "Appendix 6.1. The Construction of St. Birgitta's Cap", 130-134.
Dahl, C. L. & Lester, A. M. 2008. "Appendix 6.2. The Embroidery on St. Birgitta's Cap", 135-142.
Martinsson, Å. Birgittas huva
(http://www.textilverkstad.se/pdf/funderingar_kring_en_huva.pdf)
Medieval Textiles and Clothing 4 (eds. Netherton, R. & Owen-Crocker, G. R.):
Dahl, C. L. & Sturtewagen, I. 2008. "The Cap of St. Birgitta", 99-129.
Dahl, C. L. & Sturtewagen, I. 2008. "Appendix 6.1. The Construction of St. Birgitta's Cap", 130-134.
Dahl, C. L. & Lester, A. M. 2008. "Appendix 6.2. The Embroidery on St. Birgitta's Cap", 135-142.
Martinsson, Å. Birgittas huva
(http://www.textilverkstad.se/pdf/funderingar_kring_en_huva.pdf)