The Battle of Procyon V was a battle which took place in the 26th century of an alternate timeline. It was the final battle in a war between the United Federation of Planets and the Sphere Builders. The USS Enterprise-J led the Starfleet forces in the battle.

In 2154, as Captain Jonathan Archer was preparing to undertake a suicide mission to destroy the Xindi weapon in the Delphic Expanse, Temporal Agent Daniels transported Archer through time to the Enterprise-J, which was participating in the battle, to witness the historic occasion.

It was Daniels' hope that Archer could be convinced to abandon his suicide mission and attempt to make peace with the Xindi, informing Archer that, without him, the Federation would never come into existence and the Sphere Builders would remain unopposed. Archer was unconvinced, however, and demanded that Daniels return him to his own time. (ENT episode: "Azati Prime")

The battle also played a pivotal moment in the Temporal Cold War as it was revealed that next to the Sphere Builders, the Na'kuhl, the Vorgons, an individual known as the Envoy, and Admiral Leeta of a restored Terran Empire in the mirror universe also played roles in it, together forming an organization called the Temporal Liberation Front that advocated that time travel should not be restricted or prevented.

The Federation Temporal Agent Daniels was shortly killed before the battle by admiral Leeta as part of a 'gift' to her allies of the TLF. (STO mission: "Ragnarok")


This timeline may have been negated when Enterprise destroyed the network of Delphic Expanse spheres in 2154. (ENT episode: "Zero Hour")

Originally, the Battle of Procyon V was to be shown with an exterior view, portrayed with CGI. Due to financial constraints, the on-screen depiction of the conflict is only ever shown from the Enterprise-J's observation deck. Manny Coto regretted losing the battle footage and stated, "I think the visual effects department was pretty disappointed, because they were ready to go with the battle!" (Star Trek: Communicator issue 152, p. 50)
In Star Trek Online, the players can participate in the battle, fighting the Sphere Builders and a combined fleet of Krenim, Na'kuhl, Vorgon, and (briefly) Terran Empire vessels. The battle ends with the Enterprise-J using the Tox Uthat to destroy the Spheres.