Depending on whom you ask, David and Charles Koch are either heroes of capitalism and all of its benefits, or greedy corporate fat cats intent on lining their pockets while destroying the environment. Since around the time President Obama was sworn into office, the Koch brothers have been thrust into the political limelight, and the attention has only intensified with the rise of the Tea Party.

But how much do everyday Americans really know about these two and the industry that they've built over the past four decades? While most Americans might only know what they hear from the talking heads from both sides of the political aisle, few know about how the Koch brothers amassed their fortune.

In the following slideshow, we'll look at the history of the family and how they got to be where they are now.