The history of Freedom City can be read in the supplement of the same name, it's recent history is detailed here.
Five Years Ago - A Time of Crisis The unstoppable force that was Armageddon ravaged it's way across the galaxy destroying everything in it's path. Alien worlds cried out in pain and were then silent, their world no longer habitable. Five years ago Armageddon landed on earth and began it's cycle again. The bravest and the bold tried to stop him and failed. Several heroes and villains died in the attempt and all was lost. Johnny Rocket gathered all of the speedsters, good and bad and explained to them the concept of the Speed Force his future self had introduced him to. Together they reached a terminal velocity, unthinkable of individually and sacrificed themselves to take Armageddon into the Speed Force and out of the galaxy forever. The only speedster who survived was Kid Rocket who had been pushed to safety by his mentor at the last moment.
Four Years Ago - A Time of Healing The heroes and villains left this world, some physically to protect this world and others from mounting threats. Other gave up their costumed identities and returned to civilain identities. The world was re-built and people breathed again. But after a while a new generation of super-heroes emerged young and untrained some lasted a day on the job, some built themselves a healthy resume. With heroes came villains but with no-one to guide them their brawls became wild and uncontrolled.
Three Years Ago - A Time of Chaos Situations get worse as the new generation of heroes run riot, Adelaide gets destroyed and finally some of the older generation try and regain control. Some heroes are amenable, others either quit or become villains. Countless battles are fought.
Two Years Ago - A Time of War The older generation and their younger recruits try to build order once more. Villains are contained or have their powers stripped. The world settles down once more. And then it happens. A D list bunch of super-powered teens called "The New Revengers" have their own reality show where they "Punk'd" super-villains. This time they punk'd TNT man who was hiding from a major super-villain and was a little nuts. He panicked and began building a charge as he ran, with the heroes egging on and generally being jackass's. The result was TNT-man ran into a schoolyard just as school ended, and detonated. The resultant explosion killed over 150 children as well as 82 adults.
One Year Ago - A Time to Change The Freedom League returned and with other heroes cleaned up the mess and helped the families as best they could. The League founded the Claremont Academy to train the new generation of heroes to be more heroic and responsible for their actions.