Blackwork is a historic technique, traditionally stitched on a white or cream even weave with black thread with variations called whitework and scarletwork and is considered reversible when stitched according to the original technique. Also called the Spanish stitch or Spanish work, blackwork originated in North Africa and was introduced to Spain by the Moors. The original patterns were heavily influenced by Islamic art and were mostly geometric. While primarily associated with England, blackwork examples can also be seen in folk garments from Eastern Europe and reflect regional designs and influences.

The first mention of blackwork in England is the Miller's Tale in Chaucer's Canterbury Tales, around 1390. The carpenter's wife is wearing a dress with "embroidery [that] repeated its pattern on the collar front and back, inside and out; it was of silk and black" (1951 Penguin edition, translation by Nevill Coghill). Catherine of Aragon, 1501, popularized the technique in the British court and it was often used in place of lace. Many people used blackwork to embellish fabrics in answer to the sumptuary laws which restricted the colors, clothing and fabrics allowed for people to wear, based on profession and station in life.

The geometric blackwork designs were used extensively in Tudor and Elizabethan England and can be seen in many period portraits, often painted by Hans Holbein (1497-1543), explaining why the doublerunning stitch is often called the Holbein stitch. After Henry VIII broke with the Catholic church blackwork become more and more predominant in personal clothing. Undergarments and nightwear (an entirely new concept at the time) were frequently decorated with blackwork, as were cushions, bedclothes, etc.

During the reign of Elizabeth I (1558-1603) an English view of blackwork appeared. The motifs were delicate florals, scrolled vines, wrought iron scrollwork, and were often accented with metallic thread and sequins. Additionally, the new invention of engraved plates provided the inspiration of plants, flowers and fruits which were frequently copied in blackwork and small running stitches (called seeding or speckling) would imitate the printers ink. As fashion progressed, blackwork often decorated the undergarments designed to be seen through slashes in the outer garments.

A final type of blackwork was based on the shallowly carved grooves in Spanish and English furniture that resembled leather straps, called strapwork. This type of stitching can be seen in portraits of Henry VIII where parallel rows of stitching provide a very geometric pattern.

Blackwork was out of style by the 17th century, but was revived early in the twentieth century and can be seen in tablecloths and runners, shawls, handbags, etc. after World War I. Modern blackwork is more free form, has been adapted to canvas and needlepoint and is often combined with with other forms of embroidery and needlework.

Stitch description
Double-running stitch or Holbein stitch and is reversible. At its most basic, the thread is stitched in a line, skipping every other stitch and then returned along the same path, filling in the missing stitch, which creates the reversible effect.

Photo examples of blackwork

Sources and Further Reading
Blackwork. By Mary Gostelow. 1977.
Cross Stitch Pattern. By Dorothy Jackson. 2007.
Needlework Through History: An Encyclopedia. By Catherine Leslie
What is Blackwork? By Ann Blalock. Piecework. January/February 2004.

Reference Material
Blackwork Archives. This site has dozens of simple blackwork patterns.
Needlework Tips and Techniques. This site has a stitch library with step-by-step instructions.
X-Calibre Designs. This site has some simple online classes and instructions for blackwork.