When Speilberg made "Lincoln" in 2012, James Spader was cast as William Bilbo - an important political player who was tasked with (and succeeded in) ensuring the passage of the 13th amendment.

However, we have no portrait or photo of Bilbo, so Spader just used his imagination as to what he would look like.

Now - Bilbo may not be the most important figure in US history, however, we do know we have no verifiable photo or portrait of him.

Who's the most important historical American figure with whom we have no verifiable photo or portrait of ?