Youngblood was created by Rob Liefeld in the mid-1980s for Megaton Comics before they made their way to Image Comics in 1992. Liefeld was a fan of DC Comics' Teen Titans (the Wolfman/Perez era) and the Legion of Superheroes, and based on those interests he combined them to form Youngblood (not to be confused with Project: Youngblood from Eclipse Comics). The original Youngblood members were Sentinel, Sonik, Cougar, Bhrahma, Riptide, Psi-Fire, and Photon. By 1991, another publication origin for Youngblood came as a new Teen Titans proposal series featuring Speedy, Harlequin, a pair of Kh'undian warriors, a S.T.A.R. Labs android and an unknown character. That proposal was rejected.
At that same year Liefeld left Marvel over their strain relationship and merchandising rights for the success from his tenure on New Mutants and X-Force. He became one of the founders of Image and with his imprint studio, Extreme Studios, he revived his Youngblood comic and integrated his Teen Titans proposal to created new characters to expand the team roaster: Shaft, Badrock, Die Hard, Chapel, Vogue, and Combat.
Liefeld's idea for Youngblood as celebrity superheroes:
"...if superheroes really did exist, they would be treated much the same way as movie stars and athletes."With large team of superheroes, Liefeld came up with a solution of splitting the team into two fractions: the new characters became the home front team and the original team became the overseas "away" team.
The teams were government funded and did government operations, such as taking out a foreign leader.
To be honest, I've read a ton of these, but they made almost no impression other than Shaft was a young hotshot, Badrock was a young fun-loving guy, and Sentinel was the smart and able leader. So, I guess I can't really tell you what happened in Youngblood before Alan Moore.
According to Liefeld, the conversation about Moore taking on Youngblood went like this: "I called him up one time and said, ‘Hey Alan, how about we do a Teen Titans style book,’ and he went quiet and he goes ‘That’s what Youngblood is.’ I thought that was our Avengers-type book."
Except Moore says he never spoke to Liefeld. So, whatever. Basically, Youngblood was a clean slate for Moore to do whatever he wanted and what he wanted to do was a Teen Titans-style book for the Awesome universe.