The history of crochet is surprisingly vague and unknown. It is called crochet in
French,
Belgian,
Italian, and
Spanish, while it is known as
haken in
Holland,
haekling in
Denmark,
hekling in
Norway, and
virkning in
Sweden.
There is virtually no evidence of crochet being known in Europe before 1800. However, many suggest that crochet is a descendent of a form of embroidery called "tambouring," from the the French for drum. Tambouring was known in Turkey, India, Persia, North Africa, and China, and is believed to have reached Europe in the 1700's. In tambouring, work is accomplished with a sort of hook/needle combination tool, using fabric stretched on an embroidery ring (hence the drum name) as an anchor for the stitches. However, by 1800 the anchor fabric had been discarded, and tambouring was being worked "in the air," or as the French called it, "crochet in the air."
Mlle. Riego de la Branchardiere is known as a "mother of crochet," having made it popular in the early 19th century. She transposed lace designs into crochet patterns, and published books with these patterns so that complicated lace could be created at home. By 1840 there is evidence that Irish nuns crocheted lace, which was then sold to help victims of the Irish potato famine.
Another source tells of how crochet supposedly became well known in Italy. It is said that Joseph Napoleon I ordered all young girls in Capurso to learn crochet, so as to become more useful to their families and country. In fact, local store owners were forced to donate raw materials (threads and yarns) to schools for girls to practice on, whereupon the materials would be returned to the store.
Because crochet is so simple that it can be worked on one finger with nothing but a string, evidence of early crochet can be found nearly everywhere. Theories suggesting origins of crochet in Arabia, Tibet, South America, North America, and Scotland have all been proposed, but none have been reasonably proven.
In modern crochet patterns, instructions are written with standardized crochet abbreviations and crochet symbols.
A number of noders have /msged me about a crochet howto. While there are innumerable crochet books and websites available, its nearly impossible to teach crochet in text: see nocte's wu. Sorry!