Take a look at this 36 minute documentary posted on Youtube. I found it very interesting to see just how the BSA was formed and all the other organizations and programs that came together to make it happen. The video is posted in 4 parts.
BSA: A Centennial History Part 1

BSA: A Centennial History Part 2

BSA: A Centennial History Part 3

BSA: A Centennial History Part 4