In Star Trek: Enterprise, there was a silhouetted figure that was informing Silik and the rest of the Cabal. I don't recall ever seeing who he was, or what he was trying to do. Who was he?
He was future Archer.
This was not revealed in the show itself, but by producer Brannon Braga on Twitter in 2012, and again in 2015.
Here are the 2012 tweets:
Here is the 2015 tweet:
Archer was Future Guy. He was manipulating his own destiny from the future.
According to the 2012 tweets, had the series secured a Season 5, the Archer = Future Guy reveal would have happened then. Braga also says that future Archer's actions were an attempt "to correct history" and "repair a corrupt future".