Blackwork is a form of counted thread embroidery, which uses black or scarlet thread, on a white even-weave linen fabric.
Black work or "Spanish work", which was popular between the 13th-15th centuries, and was based on the belief that Catherine of Aragon brought many black work garments with her from Spain, although blackwork was mentioned earlier in Chaucer's Tales.
Blackwork is a development of Holbein stitch, which is a double running stitch named after Hans Holbein who featured the technique in many of his portraits. Historic black work embroidery is rarely preserved, as the iron-based dye used was corrosive to the thread. Today, blackwork uses many patterns to create sophisticated light and shaded designs.
Thanks to Pippa Foulds, Jill McIntyre and Marie Trippett for use of their images.