Sac Chieftain Blackhawk was born in 1767 near present day Rock Island, Illinois, and died in 1838. He spent most of his life as a warrior, trying to reclaim his lands from white settlers, creating both fear and admiration in his efforts. (You can read more about his life at any of the sites listed in this post, including Wikipedia.)
But the really mysterious part of his story begins with his death.
How and where he died are generally accepted to be from a two week illness, possibly malaria, and somewhere along the banks of the Des Moines River in Iowa. He was buried on the farm of his friend, Captain James Jordan, near Iowaville, Iowa.
From that point, stories vary widely regarding the manner of his burial and what happened to his remains.
The Wikipedia article (http://en.wikipedia.org/wiki/Black_Hawk_(Sauk_leader) ) contains two alternate stories: that his remains were dug up by a grave robber and eventually ended up in a museum in Iowa that burned or that the stolen remains are now buried in a Potters Grave in Aspen Grove, Illinois.
A Davenport Library article adds the interesting rumor that the remains were rescued from the museum fire and kept by an officer of the historical society. ( http://www.davenportlibrary.com/genealogy-and-history/local-history-info/the-people/black-hawk/ Although that article doesn't speculate where the remains were finally placed, perhaps it was in Aspen Grove, Illinois?
Another vote for Aspen Grove is in one of the most fascinating articles I found, the 1891 New York Times article: Black Hawk's Varnished Bones, which detailed how the bones were cleaned, varnished and stored in a box for years before ending up in the Potters Grave in Aspen Grove.
Or maybe Blackhawk was moved from the first burial site and re-buried in Iowaville, Iowa, at this gravesite, which is only a few miles from Capt. Jordan's farm. The Iowaville cemetery also contains his memorial plaque.
A detailed account of his burial in uniform and medals (found here: http://iagenweb.org/davis/BlackHawk.htm lends some credibility to the theft of only his head, since an upright burial would make the head more easily accessible.
I doubt if this mystery will be solved unless someone resorts to DNA tests, and maybe not then. Perhaps the members of his tribe already know the truth. By all accounts they made numerous attempts to recover the remains after the theft from Jordan's farm. They made have succeeded and kept his final resting place a secret to prevent further desecration.
Wouldn't you love to know who or what is buried at these various gravesites? And where exactly is BlackHawk? Maybe he's in none of them.