For the shimpaku fans out there, an amazing story of the history of the shimpaku juniper at World Bonsai Friendship Federation. If you have never read this fascinating story, I would highly recommend it.
The only information available in English says that it was a wild collected tree and is considered one of the best shimpakus that ever existed. There are no wild shimpakus of this quality left - the mountain where they were collected has been cleared of old collectable trees. Unfortunately, in the chaos of post-WWII Japan, many Imperial and priceless bonsai perished - there were simply not enough people to care for them and people had other priorities getting their lives back in order. The tree was originally called "Smoke of the Volcano".