Seasons 1-6 (History & Events)
Many of the series' flashback episodes revealed several key moments involving Olivia Pope; beginning with the fact that her affair with Fitzgerald Grant III started when she was working on his Presidential campaign ("The Trail, episode 1.06). It was during the early episodes of Season Two that Olivia was revealed as one of the members of the Defiance Conspiracy, which had Hollis Doyle masterminding the rigging of voting machines in Defiance, Ohio, resulting in Fitz being elected President. Other conspirators included eventual First Lady Mellie Grant, Verna Thornton, and Cyrus Beene, and it was a reluctant Olivia's approval that allowed the tampering to take place; something she had been regretting throughout the series.
Shortly into her time as Chief of Staff to now-POTUS Mellie Grant, Olivia found out about Fitz agreeing to become the new Command of shadowy government group B613, with the promise that he would mold it for the better. After Olivia and Jake Ballard arranged the death of the villainous Luna Vargas (who masterminded the murder of her husband, Francisco "Frankie" Vargas), Olivia gave Mellie a document to sign, which was later revealed as papers to fund a new B613, with Olivia serving as Command (unbeknownst to Mellie).
Season 7.0 (Heel Turn)Olivia began Season Seven not only as Chief of Staff, but as the head of B613, with only Jake under her employ. Beginning with the season's second episode, "Pressing the Flesh," Farid Rashad, the President of Bashran, visted the US on a mission to cement a nuclear-arms treaty, which was later made official in the episode, "Lost Girls." However, when a coup ousted Rashad as President, Mellie was set on sending troops to Bashran, causing Olivia to believe that Mellie's actions were solely as a result of her developing feelings for Rashad. In the end of the episode, "Adventures in Babysitting," Rashad and his niece, Yasmeen, were on a plane heading back to Bashran through Turkey, as he was set to return with his Presidency regained. The plane later exploded, killing Rashad and Yasmeen, and in the beginning of the following episode, "Vampires and Bloodsuckers," a flashback scene revealed that Olivia masterminded the deaths, as she made a deal with the rebels to kill Rashad.
As a result of the reveal, Olivia turned heel in the process, and she was later confronted by Quinn Perkins, who accused Olivia of being behind Rashad's assassination. Quinn later went missing, leaving Olivia fearful that she ran off and talked. With her associates on the case, the evil Olivia decided to throw them away from her and falsely claim that Fenton Glackland (Cyrus Beene's lover) was behind the abduction, stating that the relationship was an opportunity for Fenton to gain information from Cyrus and the White House. Olivia's villainous actions led to an angry Charlie abducting Fenton and torturing him, only for Huck to stop him and reveal Fenton's innocence.
Quinn was revealed to be abducted, and the following episode, "Something Borrowed," revealed that Olivia's father, Eli Pope, took Quinn and demanded that Olivia give him his freedom and his dinosaur bones in exchange for her safety. The final scenes of the episode saw Olivia meet Eli regarding Quinn, with Olivia belittling her father and calling his bluff, stating (among other things) that if Quinn has to die for the Repubic, then she has to die. The episode ends with a gunshot from Eli, with Olivia horrified that Quinn was killed, though the episodes, "Robin" and "Good People," revealed that Eli faked shooting Quinn, and that Quinn was alive and had given birth to her and Charlie's baby daughter, Robin.
Season 7.5 (Redemption)
In episode 7.10, "The People v. Olivia Pope" (which Kerry Washington directed), Olivia met Fitz in his home in Vermont, only to see Huck, Abby Whelan, Marcus Wright, and David Rosen inside, revealing that they came together as part of an intervention for Olivia. Olivia lashed out at all of them and defended her actions, while also turning down their offer for her to resign as Chief of Staff. The villainess also attempted to manipulate Huck into letting her leave, only for Huck to refuse and expressed his disappointing over what she had become. She later agreed to resign, even revealing a speech she had written, but the episode's end revealed that this was just a bluff so she could leave and engage in a tryst with Jake.
In the following episode, "Army of One," Olivia was confronted by Mellie about her role in Rashid's death, and gave her the choice of either resigning or being terminated, with Olivia turning down the chance to resign. Later on, Olivia finally learns that Quinn is alive when she visited Olivia at her home, expressing her anger over Olivia's willingness to sacrifice her life. She later ended up having to save Quinn from a sniper aiming a shot at her, with Olivia herself getting shot in the arm. The episode ended with Olivia tending her resignation as Chief of Staff, and she spent the remainder of the series as a redeemed character and protagonist once again.