Lt. Surge is known as The Lightning American. Apparently, he is or was an American soldier who fought in at least one war, during which Electric-type Pokémon saved his life. As a member of the army, Surge was a strict CO, and was rather cautious. He was a pilot as well, and used Electric-type Pokémon to power his planes, a practice that in at least one occasion saved his life. Also, Surge saved the life of one of the Trainers in his Gym who was in the army at the same time. -Bulbepedia
Well, I guess that he got the name from the war. I don't know why they put American, since there are only 5 regions. I guess that Game Freak didn't want to confuse people.
Hope This Helped :D