Why is the claim that the outlawing of crossbows contested? The only source is a "self-published thesis" which is hardly authoritative. I personally don't even know what a self-published thesis is (and I have a Phd). Isn't it just independent non peer-reviewed opinion? Note that I would have read the scholarship in said 'self-published thesis" except that it is not available. — Preceding unsigned comment added by 73.114.33.62 (talk) 17:00, 14 July 2016 (UTC)
The Latin text of Canon 29 reads: "Artem autem illam mortiferam et deo odibilem ballistariorum et sagittariorum adversus christianos et catholicos exerceri de cetero sub anathemate prohibemus." So it would depend on what exactly is meant by "ballista". Wiktionary says that you have to distinguish between an arcuballista, which is a crossbow, and a manuballista, which is a torsion-powered hand weapon. What exactly makes the two different? We have a late Roman text by Vegetius where it says: "Erant tragularii, qui ad manuballistas vel arcuballistas dirigebant sagittas". Remember that in Roman times a ballista was a rather large wheeled machine that was able to project stones. From this, smaller versions evolved that could be operated by one person, first the Scorpio (about 50 BC) and then (about 100 AD) the Cheiroballistra (Greek) or Manuballista (Latin), meaning "hand ballista". We have virtually no sources from the early medieval period. Our article History of crossbows says that "an assortment of other ancient European bolt throwers exist such as the ballista, but these were torsion engines and are not considered crossbows". Sometime around the 12th century variations of crossbows were developed in Europe which were larger than previous models and which had steel prods and were operated with winches or windlass cocking (first documented in England in 1215). These weapons were called arbalests, a medieval Franch term derived from Latin arcuballista. So the question would be what the "ballista", banned by Canon 29, actually refers to. Is it the arbalest, i.e. the winch-operated model with a steel prod? We don't know if they were already in use in 1139. Is it the smaller all-wooden model? Or is it the larger siege engine for which the term "ballista" was used in Roman times? And we would also have to take into account that the clerics who formulated the Canons were no weapons experts so their use of terminology may not be the same as that of such experts. But all this may already get us into Original Research. So to say that "the use of bows and slings (or perhaps crossbows) against Christians was prohibited" may actually the best that we can safely formulate or some other formulation that accounts for the aforementioned uncertainties. But to definitely state that the Council banned crossbows would be to choose one interpretation of the term "ballista" to the exclusion of all others and I think that, too, may be Original Research so we have to be careful here. --Proofreader (talk) 10:43, 23 April 2023 (UTC)