USS Ticonderoga (NCC-18861) was a Defiant-class Starship, originally built as a ship of the Federation Legion but on loan to Starfleet during the later stages of the Dominion War. It was manned by a Starfleet crew mostly from the USS Shiloh (NCC-74683) and a Federation Legion detachment. The Ticonderoga was commanded during its Starfleet tenure by Admiral Jeffery Higdon. (Star Trek: Black Hawk)During it's time as part of Starfleet, the Ticonderoga was part of operations with the Cha'ouw Imperial Starfleet against the Breen, newly allied to the Dominion. The Ticonderoga lead a Cha'ouw Taskforce in an assault on a Dominion taskforce and participated in the later stages of the Battle of Hades VI. The Ticonderoga lost most of its Legionnaires while in process of off-loading equipment after the battle when the ship was ambushed by a hidden Breen vessel. Shortly after this event the Ticonderoga was recalled by Starfleet and proceeded to Deep Space 9 to participate in the Battle of Cardassia Prime, the final battle of the Dominion War. However the Ticonderoga was lost and declared the last Federation Alliance vessel destroyed during the war. Higdon and a majority of his crew that survived were pick up by Chancellor Martok's flagship.
The Ticonderoga was equipped with the Type IX phase cloak, allowed when the Cha'ouw government negotiated an special amendment to the Treaty of Algeron with the Romulan Empire during the Dominion War to "allow any starship, vessel or space craft listed under the operational command of Khon of the Special Cha'ouwian Imperial House K'HIg'Den, to be equipped with cloaking device/devices supplied by the Cha'ouw". This cloaking device was destroyed when the Ticonderoga was lost during the Battle of Cardassia Prime. A Type X was secretly a joint Federation/Cha'ouw operation after Cha'ouw operatives "acquired" covertly before the phased cloak was revealed to the Romulans by the USS Enterprise-D.