Would I be able to re-create something akin to the Combine from HL2? (plus the usage of their imagery/names in the nation's creation as well?) 

Some kind of outside force that came to Earth. Different lads after the first visitors came. 

[b][i]"We should thank Our Benefactors for giving us respite from this overpowering force. They have thrown a switch and exorcised our demons in a single stroke. They have given us the strength we never could have summoned to overcome this compulsion. They have given us a purpose. They have turned our eyes toward the stars." - Wallace Breen in Half-Life 2[/i][/b]