Sean Bernard started his career as a police officer for the Vancouver Police Department. At one point he was ganged up on and beaten by some of his fellow officers because at one time he reported them to internal affairs for drug trafficking. Wolverine saved Sean and remanded him into the custody of Department H where they trained him to become one of their field agents. There he met James Hudson, the original Guardian.
James gave Sean a battle suit that was creating with the intending purpose of earth manipulation and Sean was inducted into The Flight, the precursor to Alpha Flight. There he met Stitch who took an instant liking to him. After their first mission against the villain Egghead, in which his teammate Saint Elmo dies, Sean gives up super-heroics and challenges James to wear the suit himself. James became the Guardian soon afterward.
In the alternate reality depicted in What If...Wolverine Had Battled Weapon X (What If...? vol 2, issue 62), James MacDonald Hudson is wearing the Groundhog armor when he is killed by that universe's version of Weapon X.
The Groundhog armor was originally created by Hudson when he was an employee of a petroleum company called Am-Can. The suit was designed for underground exploration and excavation, so when Hudson learned that his boss, Jerry Jaxon, was selling it to the United States military as a weapon, Hudson quit in protest. Jaxon's secretary, Heather McNeil, did the same.
That night, before security was changed, Hudson snuck back into Am-Can and stole the armor, using it to break into the company's vault and to destroy the only set of plans for its creation.
Though the suit belonged to Am-Can, the cybernetic helmet that controlled it belonged to Hudson. Knowing the armor was useless without the one-of-a-kind helmet, Hudson abandoned the armor in plain sight on a hillside near Am-Can and left with the helmet.
Knowing what Hudson had done, Heather contacted the Canadian government. Recognizing Hudson's brilliance and potential, they kept him from being sued or arrested and hired Hudson to work for them. As the founder of Department H, Hudson eventually refined the bulky, slower Groundhog armor into the sleek, form-fitting Guardian battlesuit.
Jaxon's career suffered severe consequences for the loss of the Groundhog armor, leading him to form the first Omega Flight to destroy Hudson and his team.
Groundhog was created by Scott Lobdell, Simon Furman and Pat Broderick in 1992 and first appeared in Alpha Flight Special # 1.