From Halopedia, the Halo wiki
UNSC Punic and the sister ships of her class were commissioned to help combat the ongoing Insurrection towards the end of the 25th century. Originally designated as a Space Control Vehicle, Punic was utilized to transport and sustain personnel of the Colonial Military Authority on their campaigns against insurrectionists and terrorists throughout the Outer Colonies. When the Human-Covenant War began, all Punic-class supercarriers were charged with defending the human colonies from the new Covenant threat.
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