In 'The Phantom Menace', Anakin's mother says:
There was no father. I carried him, I gave birth to him. I can't explain what happened.
So who was his father? Was it Darth Plagueis; because quoting Palpatine:
It's a Sith legend. Darth Plagueis was a Dark Lord of the Sith, so powerful and so wise he could use the Force to influence the midi-chlorians to create... [significant look at Anakin] ...life.
NOTE: I think it's Plagueis because that would tie all the 9 movies together (yes, that would also include the prequels hence would not disregard Lucas's work, which would have been a very difficult job to do). I say this assuming Supreme Leader Snoke turns out to be Plagueis.