Spartan 117
Master Chief Petty Officer of the Navy John-117 is a SPARTAN-II commando of the UNSC Naval Special Warfare Command. He became one of the most important heroes of the UNSC during the Human-Covenant war. With nearly 30 years of active duty, he is one of the most decorated war veterans in the United Nations Space Command and has earned every known medal in the UNSC except the Prisoner of War Medallion. In 2553, John-117 went missing in action after the Battle of Installation 00, when he and the current Arbiter Thel 'Vadam fired Installation 04B.
He is the protagonist and main playable character in Halo: Combat Evolved, Halo 2, Halo 3 and the upcoming Reclaimer trilogy. In the games, John is only ever referred to by name once, by Cortana, in the ending cutscene of Halo 3, before the credits. He is referred to universally by humans simply as the "Master Chief", "Chief" for short and "Sierra-117". The Covenant is aware of the power of the Spartans, and refer to the Master Chief as "the Demon", although, after the Great Schism, Thel 'Vadam and Rtas 'Vadum called him Spartan. John is referred to as "Reclaimer" by both 343 Guilty Spark and 2401 Penitent Tangent, although this seems to be a universal title given to all humans, rather than specifically referring to John-117.
Born in about 2510, John lived with his mother and father in Elysium City, on the colony world of Eridanus II. He attended the Elysium City Primary Education Facility Number 119. As a child, John had brown hair, freckles, and a small gap between his front teeth. In a memory, John recalled that his mother was "kind and smelled of soap." The would-be UNSC Marine Lieutenant Parisa was a childhood friend of John's. John once saved her from drowning at Lake Gusev, after which John promised to marry her and keep her safe. A photo of the two was also taken by Parisa's father soon after, and would be kept as a memory by Parisa long after she thought John had passed away.
At the age of six, he was identified by Dr. Catherine Halsey as one of 150 preliminary candidates for the SPARTAN-II Program. John was an ideal physical and mental candidate, standing a head taller than the majority of his schoolmates, having greater physical proportions, possessing greater strength, exhibiting superior reflexes, and having an aggressive drive for success. When Dr. Halsey and Lieutenant Jacob Keyes visited Eridanus II in 2517 to study him, they were impressed with his intellect and luck. In a final test of his viability as a candidate, he was asked to determine which side an old coin would land on. He watched the coin as it flew in the air and caught it before it could land; correctly stating which side was face-up, on the side of the eagle. Later that same year, John and 74 other six-year-old children were "conscripted": they were covertly kidnapped from their homes and replaced with flash clones, all of which would later die of natural causes to cover up the kidnappings. John, along with the other candidates, was taken to the planet of Reach. Dr. Halsey informed them of the SPARTAN-II Program and how they would be the protectors of Earth and all its colonies. The next morning John discovered his service tag, stitched into his training uniform, and his new name: John-117.
John began a new life, training with other Spartans under Chief Petty Officer Franklin Mendez. For eight years he learned history, military strategy, weapons, and was given physical fitness training. Early on, he bonded with Kelly and Sam, who would become two of the few close friends he would ever have.During his training, John quickly proved himself to be considered one of the program's top candidates. Both Dr. Halsey and Chief Mendez identified him as one of four emerging leaders within the Spartan-II group, along with Kurt-051, Jerome-092, and Frederic-104. Dr. Halsey expressed her belief the most strongly in John as having the skills and natural ability to lead the entire Spartan-II group, although Mendez disagreed, instead believing Kurt would fulfill that role.
John's first mission was against rebels in the asteroid belt of the Eridanus system, where his home world was located. He was shot in the side by live ammunition while leading his squad to capture rebel leader Colonel Robert Watts, without heavily injuring him. The mission casualty list is 11 dead rebel soldiers and an un-known number of rebel civilians. He received a Purple Heart after this mission for taking a round in the side.
As the main protagonist of the series Master Chief John-117 has had many adventures. Too many to detail here. Check out the links section for more information.