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Anakin was destined to become a Sith. We all know that. But, why? And who was his father? After seeing Episode III for the second time (quite a while ago) I put two and two together - and came up with four and a half.
Let's start with what we know, first of all:
(1) Anakin was born a slave on the planet Tatooine.
(2) His mother knew of no father - which means that either there was none, or she got drunk and/or enjoyed some Death Sticks. There is no in between.
(3) If the Jedi hadn't found him he would have never been trained to use the force - or the Sith would have gotten him.
Now in Episode III, Palpatine was telling Anakin about Plagueis and how "...he could influence the midichlorians to create... life." He then went on to hint at how Padme could be saved, and that point was lost in Anakin's head.
So, lets do a little hypothesis here -
If Plagueis did learn how to create life (and was not simply Palpatine's bluff), it makes sense that he would want to make a new apprentice, one more powerful than any other. He could also use it as an exercise to teach his current apprentice how to do so. But Plagueis is not stupid. He knows that if the new apprentice is born within the Republic's control, he would be whisked away and trained as a Jedi, and the Sith would be doomed. So Plagueis simply chose a mother in an outlying system, in the far reaches of the galaxy - one that could never bring her child to be a Jedi. A slave on Tatooine would be a perfect target. Besides, no one would question it - chances are, that most slaves on Tatooine don't have a perfect reputation.
He focuses on a certain Shmi Skywalker. He probably discovers her by either going on a scouting mission or sending his apprentice to do so. Not only does she fit his criteria, she is also fairly strong in the midichlorian count as well.
Fast forward nine years and nine months. Plagueis is dead. After his experiment becomes a sucess, his apprentice decides that he has nothing else to learn, and kills him. A few hundred years of apprenticeship is plenty. Palpatine is keeping an eye on young Anakin, as his mother named him. He is learning all the skills he'll need - anger, fear, aggression, everything that comes along with being a slave. Plus, his Force sensitivity is even more than Palpatine could have hoped for. In a year or two, once Maul is out of the way, he will go to Tatooine and fetch his prize.
Unfortunately, Jedi get in the way of his plans - again. If that stupid slime of a Nemodian could have been a little heavier on the trigger, everything would have gone as planned. But the Jedi were hardly singed, and happened to stop on Tatooine - and discovered Palpatine's future ward. He would have to think of a way to get to him.
Ten years fly by, and finally an opportunity is shown, by the name of Padme Amidala. Palpatine nudges them together skillfully, at tha same time driving the Republic apart.
Three more years, and his plan comes to a completion, better than he had hoped. This time, he didn't get his apprentice and then start slowly taking over the Republic, now his Empire. He killed two womp rats with one blast - although, his prize did get damaged in the process. Oh, well. Maybe he has a son somewhere...
