The Machete (everyone's second favorite melee weapon) was, not surprisingly, planned to be one of the weapons included in Halo 1. Surprisingly, the bunge-holes at Bungie Studios decided to cut it. Let's go in to detail.
The machete is a blade that has cut down more humans and annoying neighbors than its intended target, rainforest undergrowth. Future versions of the machete include a titanium blade and an iPod implanted on the handle. Despite the machete featuring sheer awesomeness, Bungie didn't want it mostly due to the fact that it can't slice through a Spartan's armor.
Nothing can. So, there was Halo 1.... without any melee weapons. Way to go, Bungie.