Sometime in the future, humanity has colonized many planets, in search of a better planet than nuclear ravaged Earth. One group of people, The Helghan Corporation, attempts to colonize the outlying world of Helghan. However, the planet is extremely desolate and the air scorches the colonists lungs. But the Helghan Corporation also finds Vekta, an "Eden" planet with plentiful food unlike Earth. But unfortunately the UCA and the ISA attack Vekta and forcibly conquer it, mainly because of the growing power of the Helghan Corporation. Most of the Helghan employees are arrested but some Helghan "loyalists" escape to the volatile planet Helghan. Present in Helghan's atmosphere is heavy radiation, which causes the colonists' hair to fall out and their children to be born deformed. In time, the colonists' bodies adapt, allowing them to breathe the caustic air, the average Helghast is taller, stronger, faster and more resilient than a normal human. However, due to their unique adaptions they require distinctive specialized respirators when off-world and has lent them the epithet of "Bucketheads" or "Helmet Man". The ISA also refers to them as "Higs".

http://en.wikipedia.org/wiki/Helghast

So basically Sev and company are the bad guys? I know it's a game but now I kinda feel bad for the Helghast, i hope the story has them coming out on top at the end.

no general raddick is pure evil!

Yes, they were kicked out of their homeland and forced to live in helghan where they got their military set up and their bodies effected by the harsh weather, its also why i always feel guilt when killing a helghast -_-; , more so now that the effing ISA are attacking Helghan ... the only home town left for  the Helghast.

Yes,  which is why so many people want to play as the Helghast and have asked for a Helghast campaign

when i play online i always want to be the helghast.

I hate the ISA

Turns out the Origami Killer (Alan Wake's wife) is the real bad guy.

It's weird I knew the whole story behind the games but I never played a helghast in multiplayer. I just played ISA and the red eyes don't help much(red eyes scope = headshot)