Susan Ivanova, the second child and only daughter of Sophie and Andrei Ivanov, was born in St. Petersburg on August 30th, 2230. Both women of the family were latent telepaths and thus constantly on the run from the Psi Corps. Ivanova, though hardly even a P1, spent her entire childhood moving from one school to another, trying to stay one step ahead of the Corps. She managed to avoid being detected, but her mother was eventually caught. Sophie chose to take sleepers rather than join the Corps, but unfortunately these drugs soon began altering her personality and in the end she killed herself. At this time the Minbari War had already began and a only year after Sophie's suicide Ivanova's older brother Ganya was killed in battle. Against her father's wishes Ivanova too joined EarthForce, but by the time she graduated from the academy in 2249, the war had already ended. The death of Sophie and Ganya, and Ivanova's choice of career estranged her from her father and the two didn't speak until 2258 when Andrei was in his death bed.

In 2250 Ivanova was transferred to Io where she served under John Sheridan. During the next few years she worked through the ranks without any connections or favours and had an excellent record. By 2258 she was already a Lieutanent-Commander and working on Babylon 5 as Commander Sinclair's second-in-command. Like most of the other officers on B5, Ivanova got along well with Sinclair and again like many of her colleagues, she too was at times willing to bend the rules.

When Sheridan replaced Sinclair as the station's commander, one of the first things he did was to promote Ivanova to the rank of Commander. This was partly because Sheridan wanted her to take over some of the secondary diplomatic tasks of his hands. Ivanova's first few diplomatic assignments included ending the fights between the purple and green Drazi and making a deal with the Lumati. She succeeded in both assignments even though she did break her leg while negotiating with the Drazi and only barely avoided having sex with the Lumati Ambassador.

Because of the grudge Ivanova had against the Psi Corps, she and Talia Winters - who was loyal to the Corps - were almost at each other's throats for the most part of 2258. The women had disagreements about the fate of the orphan teenage telepath Alisa Beldon, as well as many other rogues, but the more Talia lost faith in the Corps, the closer she and Ivanova became. Their relationship slowly progressed from friendship to love, but just as Ivanova began to understand her feelings towards Talia, Lyta Alexander revealed that the telepath was a brainwashed spy for the Psi Corps. The telepathic password Lyta used to prove this destroyed Talia's personality, replacing it with anotherone, known only as 'Control'. Talia was expelled from the station, but she had enough time to tell Ivanova that their relationship had been nothing more than an attempt to gain inside information. Still, Ivanova was not left without admirers - she was the object of the affections of both Marcus Cole and Lieutenant Corwin.

During her service on B5 Ivanova and Sheridan, who had known each other for ten years, formed a close friendship and she supported his decision to declare the station independent. When both Michael Garibaldi and the Captain disappeared in late 2260, Ivanova took over the command of the station until the men returned. Together with Lyta and Delenn she even tried to rescue Sheridan from Z'ha'dum.

During the Shadow War one of Ivanova's most important tasks was to find the rest of the First Ones and to persuade them into joining the Army of Light. The Shadow war was almost immediately followed by Earth Civil War, so Ivanova had hardly any time to rest. When Sheridan was captured by President Clark's forces in late 2261, Ivanova took over the resistance fleet. Together with Marcus she led the whitestars to a difficult battle against Clark's Shadow-enhanced ships. They won the battle, but the navigation system of Ivanova's whitestar was damaged and the ship collided with some debris. Marcus managed to get Ivanova out before the ship exploded, but she was fatally wounded and the doctors could only promise her a few days to live.

The last battles of the Civil War were still going on and Ivanova was sent back to B5 where she could be taken care of during her last days. Marcus, incurably in love with Ivanova, refused to accept her imminent death and desperately tried to find a cure. After hearing about the Alien Healing Machine he left the battle field, travelled to B5, broke into MedLab and donated all his life-energy to Ivanova. She was saved, but at the cost of his life.

Marcus' death was too much for Ivanova who had known about his feelings for a long time, but had rejected him because she had been afraid of being hurt again. With the Civil War now over Sheridan promoted her to the rank of captain and she re-joined Earthforce, taking command of a Warlock-class ship.

During the next twenty years Ivanova served Earthforce and eventually reached the rank of general. Still, she was not happy. In 2281, when Sheridan's friends had gathered to Minbar to bid farewell to the dying man, Delenn turned to Ivanova and asked her if she would take over the command of the Rangers after his death. Ivanova accepted the job, left Earthforce and moved to Minbar to become the third human Ranger One in the history of Anla'Shok.