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UNSC Allegiance was a frigate in the UNSC Navy. In 2552, it, along with UNSC Gettysburg, responded to the distress signal sent by Commander Jacob Keyes of the UNSC Iroquois in the Sigma Octanus system and moved to reinforce the Iroquois. Later, during the Battle of Sigma Octanus IV, Allegiance and Gettysburg intercepted a retreating Covenant carrier.
In the original edition of The Fall of Reach, the ship was called the "Alliance" on page 145 and then called the "Allegiance" on page 154. This has been fixed in the 2010 re-release of the novel, where the ship is referred to as the Allegiance in both instances.
List of appearances