The Dark Force was a group of crimefighters brought together by Val Cooper on behalf of the Joint Heads of the CIA, NSA and FBI. The Joint Heads were concerned over the power the Commission on Superhero Activities had at the time over US mutant and paranormal US citizens. Also, at the time, the government had no superhumans working directly under them and the current US teams were in disarray. The Avengers were disbanded, the Fantastic Four had major shake ups in their roster, The New Defenders were disbanded and the West Coast Avengers had split over personal issues. This left a huge gap in the current power structure and the Joint Heads together in part with the Joint Chiefs of Staff took it upon themselves to find a solution; a dark solution for a dark time.
At the time, Raven was making a name for himself as a champion of the Native American. In his Secret ID, he worked with the government as a mediator for several eastern tribes. Raven had noticed the lack of power in the superhuman community and saw groups springing up around the country hoping to become a US sanctioned team. Raven, who had worked with Cooper in the past, went to her with his idea of leading a team that would be sanctioned to stop superhuman threats. Val saw a definite fit with what the Joint Heads were looking for. Raven was approved to find his team. Their only two stipulations were:
Raven discovered Phantasm through some investigation into his accident and confronted him at his Corporate Headquarters. Raven saw the advantages of being somewhat self sufficient by having their own cash source. After blackmailing his Secret ID, Phantasm joined. They took notice of superhuman activities in the San-Francisco Bay area for their next candidates. The American had been involved in a few brawls in the area but hadn't been noticed by the general populace. While helping American handle the Wrecking Crew, a young, blond speedster named Midnight Express showed up to give a hand. Raven didn't care that he'd told them he was a mutant (Val soon discovered the error of telling a minority rights activist not to include a minority in his group). Chaos and Night Breed were also in California both in seclusion having been transformed on unrelated trips to Central America. A routine background search approved the last two members and the team was formed.
After many successful campaigns, two fateful events occurred. Chaos had been given his powers by the Secret Empire to infiltrate the US superhuman community and programmed to betray them when they were vulnerable. On a trip back from Japan, Chaos' programming took over and he attacked the group, killing Phantasm and wounding Night Breed before he escaped. Night Breed healed instantly but was revealed to be an Aztec spirit infiltrating his human body. He viscously attacked Raven, sensing the Raven spirit within him. The Raven spirit manifested and carried the wounded Raven to safety while also knocking Night Breed away from the boat.
Midnight Express and American both went their own way upon reaching California effectively disbanding the team and ending the Joint Heads' failed experiment. Val took this experiment and refined it, later using the model for her X-Factor project.
Since that time, Chaos, Night Breed, Phantasm, and American have all become criminals.