William J. Ross was a Human male who served as a Starfleet officer in the mid- to late-24th century. As an admiral, Ross took command of military operations during the Dominion War and led the Allied forces during the Battle of Cardassia, later presiding over the signing of the Treaty of Bajor, which ended the war.
Ross was the head of Starfleet forces during the Dominion War and coordinated his battle plans from Starbase 375. When Captain Benjamin Sisko and his crew arrived at the starbase, Ross appointed him the lead in a mission to destroy a Dominion ketracel-white facility using the Jem'Hadar attack ship they had captured a year prior. Later that year, he was present for and supported Operation Return, Captain Benjamin Sisko's plan to retake the key space station Deep Space 9.
Behind closed doors, Ross secretly aided the covert Federation organization Section 31 by helping their agents infiltrate the first Federation-Romulan conference on Romulus in order to place a mole named Koval at the highest levels of the Romulan government. Doctor Julian Bashir, who had also attended the conference, was deceived by Ross in a formidable plot to deliver Senator Cretak into the hands of the Tal Shiar in exchange for Koval's continued loyalty to the Federation-Romulan alliance. Cretak had been in consideration for a seat on the Romulan Continuing Committee, just like Koval; but when she was arrested by the Tal Shiar based on a scheme perpetrated by Section 31 and Ross, the seat fell to Koval, insuring his loyalty to the Federation.
When he found out, Bashir was furious and confronted Ross. Going off-record, Ross defended his actions of setting up an innocent woman by stating that he had no choice. He saw Cretak as a patriot who would not have had any remorse delivering the Federation into the hands of the Dominion and striking a separate deal with them if it served the Romulan Empire. He admitted he disliked doing what he did, however he also disliked ordering young women and men to die and felt this was the best way to maintain the alliance. In justifying his actions, Ross quoted Cicero's famous line "Inter arma enim silent leges", translated as "In times of war, laws fall silent".