Locke was an eladrin wizard and one of the major members of the Water Barons. A follower of the Raven Queen, Locke's philosophy of life was "carpe diem" and he lived life to enjoy all of the pleasures that it had to offer. In the pursuit of once and for all destroying the Far Realm god in the New World, Locke sacrificed his mortality and became a lich believing it a nessacery step in archieving the power needed to save the world.
Locke thrives on his emotions. While he is mostly known for passionate love of women (with men only one bad batch of wine away), he is also quick to action when angered. Locke believes that the ends will almost always justify the means to the point of borderline corruption. His intentions are good, but it just so happens that he is willing to do ANYTHING to reach his goals. Fortunately, he has the best interest of the colony in mind.
Also, he really wants a steam powered robot.
His original backstory was that his father had done something unthinkably horrible to his mother, and somehow, Locke had murdered his father and used his father's spine as a wand. While the details are vague, Locke would prefer them that way because the New World is an opportunity for him to move on and view the Old World as nothing but a distant memory. The Raven Queen has taught him that life must be enjoyed and to live in the past would be counter-productive to life, so he lives on.
Relationship with Pontifex
In an effort to keep tabs on Pontifex, Locke pledged his loyalty to the old lich. Locke works for Pontifex but only so he can better understand the lich's plans. In truth, Locke biding his time until he can amass enough resources and power to kill the lich for good.