Hi Lew,
congrats looks to be a fantastic functional axe. I have to agree with the view that this is not Zulu......many 'Zulu' axes seem to be Shona...whether these were gifts or war trophies seem unclear. I have found no reference to the use of an axe in battle...during the Zulu wars. However, I am wondering whether pre-Shaka (and the use of the 'shortened' spear) ...this type of weapon (an axe such as yours) may have been used instead, as a 'medium/short range' weapon.