Finding humans to drink their blood was not really difficult as it was the time of war and people frequently went missing or were found dead. Jasper had explained the situation to Simon while searching for their prey. And to Jasper's surprise he took it extremely well against other than the fact that he developed a dislike for Maria nothing which couldn't be changed with time.
While drinking blood from a man who they had found drunk in an alley Simon learned of his gift. He had read vampire novels where they had the power to control blood. Hence he tried to do the same on which he succeeded. He told Jasper about it, who also tried to do the same but failed. After discussing it with Maria they understood Simon's gift, it was hemomancy. Ironic, Simon thought, as a person who used to hate blood now has it as his best weapon and will depend on it to live.
After feeding enough that they would stay tame, Maria started to tell them about the vampires and vampire society about how sunlight makes their skin shine unnaturally but doesn't effect them in any other way, how they would stay the same age, about Volturi that is the largest and most powerful coven of vampires. Who took it upon themselves to enforce the laws of the vampire world. They are considered the royalty of vampire world. She also told them about the history of her coven how a war in the south started because of a vampire who rose to power in the South by forming an army of newborns, wiping out neighboring covens and pressuring others to create their own newborns in order to defend themselves. This continued until the matter could not be ignored and Volturi swept in cleaning the house, giving the South a short time of peace until others started forming their own armies again and attacking unsuspecting covens like the her coven which left only Maria alive. Defeated and alone, Maria joined forces with two other vampires Lucy and Nettie, who had also lost their territories and covens in the same manner. Deciding to create a newborn army of herself she stumbled across Jasper, who seemed a perfect fit for the army as he knew how to fight and was competent in leading armies.
Jasper who was still not used to his power of pathokinesis was strayed to agree to her request of help as he felt her anger, sadness and injustice that she felt. Simon on the other hand didn't really care about it as he had just decided to follow Jasper until he found something he wanted to do.
With Maria in lead they started to create an army of newborn, Maria had already earned them not to make a cursed child as it will only spell their doom. Overnight they made nearly 34 newborns and went to the place where they would meet up with Lucy and Nettie who had been making an army of their own.
After meeting up with them they had a total army of 97 newborns.
The attack on the covens who had taken away their territories started. Simon saw no difference in the battle he had just had this morning and the one they were fighting right now. It was simple kill or be killed and Simon had no intention of being killed.
Meanwhile Jasper had a much easier time and simply went wild all his grace that he had as a major was nowhere to be seen. He was heavily being influenced by the anger and bloodlust of the other vampires he didn't feel any sadness or grief as he was surrounded by newborns who hardly thought of anything other than blood.And just tore one vampire after another.
Seeing Jasper become stronger due to his gift Simon thought of how his gift could help him. He concentrated and found that all newborn vampire had blood in their bodies which he could feel. He tried to manipulate it it was too weak to be of use. Then he concentrated on his own blood he increased the speed of his blood flow which caused his body to redden but he felt a surge of power. He too entered the heart of the battlefield and started to claw into his enemies ripping them apart.
The battle continued until all the vampires had died.
The last few standing were Maria, Lucy, Nettie, Jasper, Simon and a few other newborn vampires that had been turned by them.