Guardian

Jim Harper grew up as a poor boy in Metropolis' "Suicide Slum." He and his best friend Leo sometimes engaged in petty theft, but after one such act, Jim was caught by a man who called himself Nat Milligan. Leo got away, and JIm did not see him again for years. Milligan believed that boys could escape poverty through careers as athletes, and he trained Jim over the succeeding years in hopes of turning him into an Olympic champion. Later, Jim would discover this man was actually Joe Morgan, who had trained the original Atom and Wildcat.

Eventually, Jim Harper returned to suicide slum to discover that Leo had become a gangster. When Leo was killed before Harper's eyes, Harper vowed to fight the way that Suicide Slum destroyed people's lives. He told Milligan that he was joining the police force and Milligan fell into despair at the thought of losing another protege.

As a rookie policeman, Harper was assigned to Suicide Slum. One day, while off duty, He was beaten up by vengeance seeking thugs. To protect himself, Harper obtained a costume, a helmet and an antique shield from a costume shop and, in costume, captured the thugs, who turned out to be wanted kidnappers.

The masked Harper called himself the Guardian, saying he was a "guardian of society."

Later, officer Harper captured four newsboys who were robbing a hardware store. To prevent them from being sent to an institution, Harper instead persuaded the judge to make him the legal guardian of the four orphans, who thereafter had many adventures as the Newsboy Legion. The boys often suspected that Jim was the Guardian but they were never able to prove it.

During World War 2, the Guardian was a member of the All Star Squadron. Harper eventually retired as the Guardian when he becam a polic detective. The Newsboy Legion members, now adults, went to work at the DNA project, a genetics laboratory. After being shot by a criminal, Harper confessed to the former Newsboys that he had indeed beeen the Guardian. Harper died, but at the DNA Project Cadmus, the Legionnaires made a clone of Harper that possessed his memories. This clone became the Golden Guardian.

It was later revealed that Jim is Roy Harper's uncle.

Jake Jordan had used the matntle Manhantan Guardian for a time.

For a time The Golden Guardian was active but eventually killed. There was another clone that began operating but soon disappeared along with the rest of Cadmus after a altercation with Amanda Waller and then president Lex Luthor his where abouts became unknown.

Possibly as a result of Infinite Crisis history was altered showing that the original true Jim Harper was not killed in action but shot in the head by Jonathan Drew after discovering plans to clone him.  It has also been revealed that the original clone off Harper survivied and left Cadmus early on. The Golden Guardian(s) seen in that time were all clones that died in a year. Jim Harper was in fact in the town of Warpath near the Mexico border where he helped officer Greg Saunders sometimes. The original clone of Harper decided to move to Metropolis and began living with his adopted daughter Gwen (a female clone of him that he rescued)  he was asked to join the Science Police after the deaths of two of their officers at the hands of two New Kryptonian criminals by Science Police Officer Rachel to replace the two dead officers.  Jim Harper now serves the Science Police as the Field commander.  Superman who was leaving Earth to go under cover in New Krypton asked Jim Harper to mentor Superman's friend Mon-El who had now become the temporay Metropolis superhero in his absence.