From Halopedia, the Halo wiki
During the Insurrection, Peter Moritz was an insurgent responsible for multiple bombings and ship hijackings in the Inner Colonies. At some point, Andrew Remo introduced Peter to Staffan Sentzke who informed him of his daughter's kidnapping. They became lifelong friends and eventually settled on the colony world of Venezia, where they established a centralized insurrectionist government. As the years progressed, Moritz changed his focus from overthrowing Earth's control across human-controlled space to keeping Venezia out of the UNSC's line of sight.
In January of 2553, the UNSC Ariadne arrived near Venezia due to reactor complications and sought help from the colony. Moritz refused to aid the ship, fearing that it was ploy to insert UNSC personnel unto the planet. As a result the Ariadne was destroyed with all hands lost. Months later, in April, he visited Sentzke at his home. Staffan informed him that he had purchased the Covenant battlecruiser Pious Inquisitor. Peter was nervous about what the UNSC would think of this. Sentke assured him that he wouldn't do anything rash with the ship and that it was an asset. When Sentzke stated he was looking for a human crew, Moritz told him about a pair of UNSC deserters that arrived on Venezia, whom Nairn said had experience with Covenant ships. Their discussion ended and the two parted.
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