Third in command of Babylon 5
, Corwin was initially a technician in C&C until he was promoted to Lieutenant
and served beneath Susan Ivanova
When Babylon 5 joined with the Interstellar Alliance, and the The Station fell under the command of Elizabeth Lochley, Corwin served as Second in Command, and Senior Operations Officer, replacing Susan Ivanova.
Even after Babylon 5 seceded from the Earth Alliance, Corwin and the rest of the Babylon 5 staff (aside from Captain John Sheridan, Commander Susan Ivanova, Security Chief Michael Garibaldi, Dr. Stephen Franklin, and Zack Allan) continued their service as Earth Force Officers.
In the Episode, "Objects at Rest", Corwin remained on Babylon 5 to continue the vision that Jeffrey Sinclair, John Sheridan and Delenn started.
Corwin first appeared as a nameless Technician in "Legacies".
Corwin was given his name and rank of Lieutenant J.G. in "A Day in the Strife"
Corwin is promoted to Full Lieutenant in "Exogenesis"
In the same Episode, Susan Ivanova approaches Corwin about the possibility of joining the Conspiracy of Light, it is not determined in this episode, however, he eventually does come along after Babylon 5 secedes from the Earth Alliance.
Corwin was promoted to replace Susan Ivanova
as second in command in "No Compromises
Corwin is last seen on Babylon 5: The Series
in "Objects at Rest
An Aside: The character arc of David Corwin was originally designed to be the arc of Susan Ivanova at the time of the Pilot "The Gathering", however when the character Laurel Takashima was not carried over to the series, the arc had to be edited, and a weaker Corwin arc created.