Howdy MB,
The Unimog was first built right after WW 2 by a company by the name of Boehringer as an agriculture vehicle to help Germany recover from the war. Mercedes took over and started production in 1951. The Mog is still being built. Here is another site for you to look at.
www.rockymountainmoggers.com
Also check out the Mog websites I have posted in this forum. There are a couple videos on the websites. Welcome to the forum.