Agile has been around since the mid 1990s but the principles and values go way back.  As a matter of fact, I believe that the Pyramids were the first iterative development project.

A pyramid, as you may know, is a tomb for a Pharaoh.  We learned this in grade school.  But did you ever consider how they were able to be sure to have the pyramid done when the  Pharaoh died? One theory is that they did it by building the pyramid incrementally. They started with a small pyramid, just a tiny little pyramid.  Then they added a layer of stones around the outside of the first layer, then another, and another. Each layer of stone laid around the next to basically “skin” the pyramid with another layer.  Building this way the Ancient Egyptians could have the pyramid ready anytime.  If Pharaoh died – Viola- The pyramid is ready.

I wish I could take credit for making this observation but I read it somewhere a few years back.  If you know who made this observation first please let me know so I may credit them for their astute observation.