Mentioned in the movies:
Darth Plagueis
Darth Sidious (Senator/Chancellor Palpatine)
Darth Maul
Darth Tyranus (Count Dooku)
Darth Vader (Anakin Skywalker)
In the Expanded Universe (comics, novels, games, etc.), there are dozens more, e.g. Darth Bane, Mara Jade, Asajj Ventress, Darth Talon, Darth Sion, Darth Malak, Darth Revan, etc.
Sounds like you're referring to Captain Rex from the TV series "Star Wars: The Clone Wars"
No one person really started the Dark Side of the force. It always was an aspect of the force and the force has been in the galaxy as long as there has been life. The first Jedi to use the dark side was Xendor. His choice to use this aspect of the force would lead to the formation of the Sith as we know them today.
That episode is Season 3 Episode 16 "Altar of Mortis." (And actually, the only reason why Ahsoka turned evil was due to the living embodiment of the dark side of the Force corrupting her with a spell in an attempt to get Anakin to join the dark side)
Revenge of the Sith focuses on Anakin's turn to the dark side and becoming Darth Vader
star wars theme song(of course)"unknown"my little buttercup turn the ship around and where are the cowboys gon
One can find more information about the dark side by going to the IMDB website. The website has information on Star Wars and characters who joined the dark side.
the dark side
star wars movie
It changes all the characters' force into Dark Force, or Sith. also turns some light sabers red.
There are billions of Star Wars characters.
clone wars
Luke doesn't die in star wars 7. He marries Mara Jade. There will be more chances of danger and he will turn dark side. But he does not say on the dark side
Lego Star Wars The Yoda Chronicles - The Dark Side Rises - 2013 was released on: USA: April 2013
Anakin Skywalker Asajj Ventress Darth Tyrannus
Two... light side.... and semi dark side.
Darth Vader level
Jump down the staircase when you are at Vader and you will fight him witch will unlock the dark side ending.