Hi,
looks African, the metal winding around the shaft seems to suggest so. Seems to be designed as a 'thrower'. The 'head' would be a little light but, the wooden shaft 'swelling' at the business end would create better balance. The tapering metal shaft is nicely done, if it is forged. Probably a hunting spear but I have little idea whereabouts in Africa or Tribe where this spear could have originated, sorry.
Your monkey friend seems alittle upset that he's run out of beer....not a good idea when he's so well 'armed'
Regards David