"Okay Axis! Here we come!" cries the Invaders before batte! At the end of 1941, as the United States enlisted in World War II, Captain America, Bucky, Human Torch, Toro, and the Sub-Mariner joined forces to oppose Master Man, a superhuman American Nazi who attempted to kill English Prime Minister Winston Churchill. Churchill was so impressed by the heroes he encouraged them to remain together as the Invaders. The Invaders took aim at the superhuman agents of the Axis powers, as well as engaging the enemy on the battlefield.
The Invaders soon moved their operations to England. While battling Baron Blood (Falsworth), they met Lord Montgomery Falsworth the original Union Jack of World War I. He joined their team, only to be incapacitated when Baron Blood shattered his legs. Lord Falsworth allowed the team to use his mansion, and his daughter joined as Spitfire. Eventually, Brian Falsworth joined the Invaders as Union Jack, taking his fathers alias.
Later back in the U.S. to face the threat of the Super-Axis, the Invaders brought the Whizzer, and Miss America of the Liberty Legion into their ranks, then admitted Blazing Skull and the Silver Scorpion during their fight with the renegade heroes of the Battle-Axis. Shortly afterward, they joined several other heroes in a mass attack on enemy territory. Among the long list of threats that the Invaders faced during WWII were the alien Gods from the Stars, the armored Teutonic Knight and Iron Cross, the android Firebrand Squadron, the cloned N-2, and an unnamed Nazi war machine.
As World War II came to a close, the Invaders suffered their greatest loss when both Captain America (Rogers) and Bucky (Barnes) were seemingly killed. However, the government appointed a new Captain America and Bucky (Davis) to fill their roles for the remainder of the war. At the war's end, the remaining Invaders founded the All-Winners Squad.
In recent years, the Red Skull, posing as US Secretary of Defense Dell Rusk, tricked the Thin Man into organizing a new team of Invaders against the Axis Mundi, a Neo-Nazi organization. The Thin Man constructed the battleship the Infiltrator to oppose them, unaware that the Red Skull intended to steal it to equip the Axis Mundi. They conquered the nation of Mazikhandar before realizing their error but retained control of the Infiltrator. The Thin Man maintained contact with other WWII era heroes such as Blue Diamond, Nomad, Red Raven, and the Vision (Arkus). Eventually it was revealed that the new android member Tara, was in fact a Trojan horse member of the Axis Mundi, unbeknownst even to her. In the resulting incident the Torch sacrificed his life to save the others, and the Thin Man drove the Infiltrator into a dimensional rift to finally destroy the machinations that the Red Skull as Rusk had enacted.