California boasts America's largest economy and would rank ahead of the UK, France, and India in terms of GDP if it were a sovereign country. Instrumental to the Golden State's financial prowess is its many globally renowned businesses, which include tech giants as well as entertainment, retail, automotive and energy juggernauts. Together these firms turn over trillions of dollars annually. We've rounded-up the most prosperous of them all, from the oldest to the most recently established.