General Thaddeus E. Ross was born into a family with a proud tradition of military service. Both his father and his grandfather served heroically in pas American wars. As a boy Thaddeus immersed himself in military history, and he learned how to fly by barnstorming at country fairs.

As a young man, Ross enlisted in the military, graduating first in his class at West Point. He married Karen Lee, the daughter of his commanding officer at the time. Ross rapidly rose in rank to captain and then major while serving in his first war. Ross made a great reputation as a leader in combat; he received his nickname when his troops said he "struck like a thunderbolt" when leading them into action.

After the war, he was stationed at the nuclear research facility at Los Alamos, New Mexico. There he met nuclear physicist Brian Banner, the father of Robert Bruce Banner.

Ross had risen to the rank of colonel by the time he was sent to his next war, during which he became a general in the U.S. Air Force (Ross never rose beyond three-star general). As he gloried in combat, he was dissatisfied with the "desk jobs" he was given before and after the war.

Ross's wife, Karen, bore him only one child, his daughter Betty. Karen died when Betty was in her early teens. General Ross came to command Desert Base, New Mexico, a missile base and nuclear research site. He resented the fact that Bruce Banner, a civilian, was appointed supervisor of the gamma bomb project. Moreover, the general had contempt for the unathletic, intellectual Banner for failing to live up to Ross's own vision of true manhood. Making matters worse for Ross was the growing attraction between Banner and Betty, whom he hoped would marry a military officer.

Banner was transformed into the Hulk as a result of intense radiation exposure during the first test of the gamma bomb. The savage Hulk quickly became a menace, and Ross began his long career of hunting the Hulk. Banner's frequent, unexplained absences made Ross suspect Banner of treasonous activity and of a possible alliance with the Hulk himself. To prove his suspicions, Ross brought Major Glenn Talbot to Desert Base as the new security chief. The Pentagon designated Ross as head of Operation: Hulk.

Even after Banner's dual identity became public knowledge, Ross continued his pursuit of the Hulk, causing Banner to become a hunted fugitive. Ross incorrectly suspected that Banner controlled the Hulk and was thus an international menace to national security. At times over the years, Ross succeeded in capturing the Hulk or Banner, but more often the Hulk thwarted the general's attempts to capture or kill him, or, even if captured, the Hulk soon managed to escape. Embittered by these failures, Ross grew even more determined to put an end to the menace of the Hulk.

In addition to the Hulk, Ross found himself in conflict with other superhuman foes, most notably the Leader and the Abomination. Invariably these menaces were defeated by Banner or the Hulk, forcing the general to regard the Hulk with a grudging respect. When Banner actually did gain control of the Hulk, Ross reluctantly approved of his marriage to Betty. However, the Leader sabotaged the process, transforming Banner back into the savage Hulk before they could be wed. Ross himself was injured in the ensuing conflict.

Subsequently, the U.S. Government commissioned Operation: Greenskin, based out of Hulkbuster Base, a special site for operations to capture or kill the Hulk. Due to his experience, Ross was given command of the base and its troops, commonly referred to as the Hulkbusters. The primary directive of the Operation was to capture the Hulk and cure him, as well as study the effects of radiation on the human body to bring about major medical breakthroughs.

Ross was greatly pleased when Betty instead married Talbot after she had come to believe that she would never have Banner as her husband. Desperate to keep the Hulk from ruining Betty's life, Ross illegally bargained with the Abomination against the Hulk, although the Abomination met defeat.

Ross led a team of Hulkbusters to pursue the Hulk into the Arctic Circle where he was captured by the Gremlin, a Russian agent. Ross was freed by the combined efforts of Glenn Talbot and Air Force colonel Jack Armbruster. However, in the process, Talbot was captured in his place and presumed by the others to be dead. As a result of his capture, Ross was relieved of command of Operation: Greenskin and replaced by Armbruster. Though officially on leave, Ross often accompanied Armbruster on Hulkbusters missions. After Armbruster was killed, Ross and S.H.I.E.L.D. agent Clay Quartermain led a team that rescued Talbot.

Ross then rededicated his command post as Gamma Base, focusing even more on gamma research. However, injured when the Leader took over Gamma Base, Ross was pushed into a nervous breakdown by Moonstone, who used her psychiatric skills to crumble his psyche. Ross spent a length of time under the care of Doc Samson. During this time, Betty and Glenn Talbot were divorced, the funding for Gamma Base was cancelled, and Glenn Talbot died while trying to kill the Hulk.

Ross eventually recovered and returned to active duty, bent on avenging his protégé Talbot's death, as well as getting revenge on the Hulk for his nervous breakdown. Ross was unable to regain funding for hunting the Hulk, but the President made him a special advisor at the Pentagon on matters relating to the dangers posed by the Hulk. However, soon after, Banner regained control of the Hulk, and the President pardoned him for all of his past offenses.

Still convinced the Hulk was a menace, Ross made an alliance with both the Abomination and MODOK. This effort, too, failed; when Betty Ross learned of these events, she was appalled, accusing her father of treason. Overwhelmed by shame, Ross nearly committed suicide in his office in the Pentagon. However, he instead dropped out of sight, during which time he was dishonorably discharged. Ross became a drifter, sinking increasingly further into insanity.

Upon learning that Betty and the seemingly cured Bruce planned to marry, Ross attempted to stop the wedding at gunpoint. Ross shot Rick Jones when he tried to stop him, but Betty confronted her father and persuaded him to let the wedding proceed. Ross was hospitalized and placed under psychiatric care.

Ross's old ally Clay Quartermain enabled Ross to participate in a n experiment that would give him the powers of Zzzax. However, the experiment went awry and Zzzax absorbed Ross's consciousness, after which the Ross-controlled creature attacked Bruce Banner and Rick Jones, who had taken a Hulk-like form at the time. Ross/Zzzax fled after being forced to recongize that he himself was now a monster, and Ross's mind returned to his own body. Still retaining some electrical powers, Ross sacrificed his life, using that energy to destroy the mutant Nevermind which had briefly terrorized Gamma Base.

Ross's body was taken by the Leader, who had the Soul Man restore it to a semblance of life as a nearly mindless servant, and placed it in the Redeemer armor after its previous occupant's death. After being exposed as the new Redeemer, Ross was nearly killed again during a battle with the Hulk, who believed him to another of the Leader's tricks. He was recovered by the Troyjans, who fanned the spark of life within him and brought him to the Leader's Freehold Base where he eventually regained his memories and personality. Not long after this, Ross was restored to his previous position of Air Force General.

Ross blamed Bruce for Betty's apparent death from radiation poisoning and went on to lead a new incarnation of the Hulkbusters. However, while pursuing the Hulk he confronted the Abomination and learned that it was actually he who had poisoned Betty. Afterwards, Ross made his peace with Banner.

Later, Ross was coerced into working with General Ryker against the Hulk, but ultimately Ross helped the Hulk free himself and defeat Ryker's plot. Soon after, Ross goaded the Hulk into seeking out and badly beating the Abomination. After using his former enemy to gain the vengeance that he himself lacked the power to accomplish, Ross allowed Banner to leave in peace.