Fifteenth century crossbow. © Wallace Collection.
For several centuries, the crossbow earned a reputation (not wholly undeserved) for villainy--crossbows were used against no less than 3 English monarchs during the 12th century. In fact, the crossbow was twice the subject of papal bans (in 1096 and 1139). The only exception was against infidels.
Outside of England, where the longbow was seemingly mandated as a national pastime, the crossbow was favored for several notable reasons: it required very little training; its ammunition was comparatively less expensive; and, it could be kept fully spanned for a considerable amount of time. By contrast, the English warbow took many years to master and its wielder could do little more than (mightily) draw and shoot.
Crossbowmen were extensively employed by the English for garrisoning towns and castles during the Hundred Years War. They earned a daily wage of 8d per day--the equivalent of a man-at-arms and notably more than the 6d earned by the more heralded longbowman. The higher wage is due to the fact that campaigning soldiers typically owned their own equipment and crossbowmen were almost always very well-armoured.
The lath, or bow, was often made of Yew like the longbow, except, for a time, it was not composite, or made from multiple layers glued together. This was likely due to the earlier limitations of the lock mechanism prevented greater draw weights. Early composite laths were generally of wood backed by horn and/or whalebone and wrapped in sinew. Steel laths appeared in the early 14th century. However, they were to remain low-powered until the development of steel production allowed for cleaner metals with higher carbon contents. Prior to that time, steel laths could break under the strain of a high draw weight, which would likely cause considerable injury to the wielder. Many were painted or treated or covered to prevent rust. Some surviving examples were fitted with safety cords bound around the lath and secured with glue to help contain metal shards in the event of breakage.
The gaffle, often called a goat's foot lever, appears in art from about mid-14th century. It provided a mechanical advantage of about 5:1.
Regardless to how the crossbow was viewed on the battlefield, it was ever a high-status hunting weapon. The crossbow of noblemen sometimes had a veneer of intricately-carved stag horn and/or elaborate patterned inlays. I recently commissioned a fifteenth-century hunting crossbow from Danilo "Tod" Todeschini of Tod's Workshop. Tod's expert craftmanship is featured extensively in Mike Loades's bookThe Crossbow. The gallery below contains a dozen photographs taken from Tod's Workshop and are representative of the style of hunting crossbow I have commissioned.
Loades, Mike. The Crossbow. Osprey Publishing, New York. 2018.
Todeschini, Danilo. Tod's Stuff. http://www.todsworkshop.com.