Originally known as ORION Generation II, the Spartan II project was an effort made by ONI to further the original ORION project and to create biologically augmented super soldiers. The Spartan II program was the first in a series to meld advanced exoskeleton-based technology to help form a superior soldier.
In around 2510, Doctor Catherine Halsey of ONI-III, conceived the Spartan II program in an attempt to end the widespread Insurgency that frenzied throughout the colonies of Earth. Originally intended for 300 subjects, there was only a budget allotted for 150 suitable candidates. These candidates were children of the various planets of UNSC controlled space. The children were then abducted from parks and schools, one by one, and flash clones were used to replace them. These Flash Clones were made from experimental technology, and all of which died from natural causes due to having no immune system and organ defects.
The children were put through training at the age of five and six. During their training, ONI put the children through hormone treatments. At the age of 14, in 2525, the children began undergoing biological augmentation treatments of which only 33 survived without any adverse side effects. Those with adverse side effects that survived were rehabilitated and seeded into ONI and the UNSC.
Now, the newly made Spartans were fitted and given Mjolnir armor; at about this time, the Human-Covenant War had already begun