Zaeed was created by Mac Walters for the Mass Effect 2 squadmate DLC pack Zaeed: The Price of Revenge. His comic book debut was in Mass Effect: Foundation #11, written by Walters and Jeremy Barlow with art by Tony Parker.
Zaeed was a co-founder of the prominent mercenary group called the Blue Suns, though very few people know this. Zaeed managed the mercenary work while Vido was in charge of the finances. Things went well until Vido started hiring batarians to the Blue Suns, reasoning that it was cost-effective since they were willing to work for low wages. Zaeed strenuously objected to this, condemning the batarians for the Hegemony's vindictive campaign of terrorism against human colonies. Years later, Zaeed would sum up the argument with the words "Cheap labor, he said. Goddamn terrorists, I said."
Vido turned Zaeed's men against him, getting six mercs to hold Massani down so Vido could shoot him in the face, leave him for dead and take sole command of the Blue Suns. But Zaeed survived, forcing himself to stay alive out of sheer rage until he could secure medical attention. He received skin and muscle transplants to replace the part of his face blown away by Vido's gun, and as a result, a portion of his face is discernibly different from the rest of it.
Almost twenty years later, Zaeed got the chance for revenge when Cerberus contracted him for the secret mission beyond the Omega-4 relay. With Commander Shepard as an ally, Zaeed stormed the Blue Suns' refinery on the planet Zorya, killed Vido's men, and set him ablaze as punishment for his betrayal.
Despite his chosen profession, Zaeed does have a recognizable code of honor. He will not accept jobs from slavers or terrorists, and has on several occasions conducted raids against slave trafficking rings himself. He is somewhat of a romantic when it comes to his attitudes about death and warfare, something that surprised Samara a great deal, given his gruff, hardened exterior. During the Reaper War, Zaeed busied himself by taking on any and all jobs that damaged Cerberus interests, and rounded up several of his old mercenary buddies to assist with the war effort.
Zaeed's most prized possession is an M-8 Avenger assault rifle nicknamed Jessie, part of a discontinued line. For years, it was his go-to firearm in the field, and he once boasted that more men had been slain by Jessie than had died in the Skyllian Blitz. After the M-8 line was discontinued, he was forced to retire Jessie since spare parts were hard to find, but during the Reaper War, he made it a point to hunt down spares, determined to fight at least one last battle with his faithful rifle.