On modern versions, a red sash or tassel is attached at the joint of the pole and blade. Variations include having rings along the length of the straight back edge as found in the nine-ring guan dao, having the tip curl into a rounded spiral as in the elephant guan dao (literally Elephant Knife", or featuring a more ornate design as exemplified by the Dragon head guan dao. However, apart from the "Elephant knife" none of these variations seem to have historical ground.
According to legend, the guan dao was invented by the famous general Guan Yu during the early 3rd century AD, hence the name. Due to his large stature, he was able to wield such an imposing weapon and developed the guan dao into a versatile tool. Guan Yu's guan dao was called "Green Dragon Crescent Blade" (青龍偃月刀) which weighed 82 Chinese jin (estimated 49 kg.)
However, historically speaking it is likely that Guan Yu most likely would not have used a dagger-axe (ji) . While the famous novel Romance of the Three Kingdoms by Luo Guanzhong describes him as wielding the guan dao, this description might be an anachronistic one, as there is no illustration to show that it was ever used prior to the 7th century, (Tang or Song dynasty) when it was first illustrated in the military manual Wujing Zongyao. The guan dao, therefore, was likely neither invented nor ever used by Guan Yu, meaning that it is somewhat of a pop culture-derived misnomer. Some historians believe that the guan dao was simply an uncommon, rare weapon prior to the Song dynasty and was thus not illustrated before then but without historical proof this will remain speculation.
While it could be used from horseback, and was so by the Koreans, the guan dao could also be used by infantry as an anti-personnel and anti-cavalry weapon. The modern guan dao as adopted by martial artists today usually weighs between 2 kg and 10 kg (5 and 20 pounds), while it is said that Guan Yu's original guan dao weighed between 50 and 100 kg (100 and 200 lb). During the Qing dynasty some extraordinarily heavy versions of guan dao were made for use in military examinations: a candidate had to be able to wield a weapon weighing 80, 100, or 120 jin (48, 60 or 72 kg) in order to pass. The weight of Guan Yu's weapon was probably mis-estimated based on some of these examples.
Historical guan dao, for the most part, were largely used by Chinese infantry, in the Qing it was only used by the all Han Green Standard Army. Apart from that, the lack of standardization of the antique examples that survive to today seems to indicate that at least from the 19th century it was popular in the civilian martial arts realm as well.
Forms utilizing the weapon in nearly all traditional styles of Chinese martial arts, emphasize strong slashing movements and momentum to keep the heavy blade moving through a series of spinning cuts. The considerable weight of the weapon also makes guan dao forms good for training the overall conditioning of the body.