Preston Cole

Admiral Preston Cole was a UNSC Naval officer during the Human-Covenant War. He is best known for his role in creating the Cole Protocol, a central UNSC law of the Human-Covenant War.

Battle of Harvest
In 2531, Cole, who was a Vice Admiral at the time, led a task force to retake the Harvest System during the Second Battle of Harvest, after the returned to Reach, badly damaged from first contact with the Covenant.

During the ensuing battle, he lost two thirds of his fleet and only achieved "victory" through a last minute tactical inspiration. Though Cole was able to achieve a psychological victory over the Covenant, the Epsilon Indi system was lost nonetheless. The decisive advantage of the superior Covenant technology and tactics convinced him to issue the Cole Protocol.

The Cole Protocol
The Cole Protocol, otherwise known as United Nations Space Command Emergency Priority Order 098831A-1 was a law to prevent the Covenant from finding the location of Earth. Essentially, it is an order preventing Covenant retrieval of data that contains the location of Earth, and forbids retreating vessels from setting course to Earth, as the Covenant is able to track Slipspace travel and find Earth's location.

The policy also states that to prevent capture, any UNSC or Human vessel is to self destruct, after wiping all data matrices, to prevent the advance of the Covenant, and make sure they can not find Earth.

The first mention of the Cole protocol occurs in the book Halo: The Cole Protocol where Lieutenant Jacob Keyes used it to escort 1 million people to Falaknuma, 18 Scorpii using Section 4. The next time it was mention was when Cortana and Captain Jacob Keyes are talking on the Pillar of Autumn's bridge. Cortana informs Keyes that the Covenant are closing in on them fast. Keyes then initiates the Cole Protocol Section 2, crash landing the Autumn on Installation 04 and the ensuing events make up Halo: Combat Evolved.

The Outer Colonies
Cole returned home to discover that he had been promoted to Admiral and was known as a hero for his victory at Harvest. After Harvest was lost, he was ordered to defend the rest of the Outer Colonies. Despite his strategic brilliance, the Covenant won simply because of their overwhelming numbers and superior firepower.

From 2531 to 2535, Cole's fleet met defeat after defeat, until most of the outer colonies were destroyed by 2535.

Trivia

 * Admiral Cole's fate is unclear, though in Halo: First Strike a painting entitled "Admiral Cole's Last Stand" is described. This could possibly be a depiction of the events that led to his death.
 * The Cole Protocol was an effective law of the United Nations Space Command up until October 20th, 2552, when the Covenant found Earth during the First Battle of Earth, there, by rendering the Protocol useless..
 * The date 'October 20th, 2552' could be another 7 reference. 2+0+2+5+5+2=16, 1+6=7.
 * He promoted Lt. Keyes to the rank of Commander, for his protection of 1 million people in the book The Cole Protocol.