Short answers, pulled from the story.
Game planning began in the summer of 2004 when a small group of about six developers started with a clean slate. They spent more than a year brainstorming ideas for what might make a good game.
Sam Witwer provides Starkiller voice and likeness. He secured the role by demonstrating to developers deep understanding of character and imbued him with sense of humanity.
As of July 2009 it had sold six million copies. The Force Unleashed was both fastest-selling Star Wars game and LucasArts fastest-selling game.
Following Walt Disney Company acquisition of Lucasfilm in 2012 game became part non-canonical Star Wars Legends continuity in 2014. Alternative origin for Rebel Alliance and Galactic Civil War given in other forms of Star Wars media such as Star Wars Rebels.