|Diane and Catherine|
|“||I never thought a mother could do this to another mother's child.||”|
— Catherine to Diane in Banished
Early History Edit
Catherine knew Diane before she got married or became Queen of France; however it wasn't until after Henry married her that he began his affair with Diane. The affair caused lots of tension and feelings of hatred to rise between them, since Catherine felt that Diane stole her husband from her.
Season One Edit
In Fated, Catherine discovers from Kenna that Diane plans to have Bash legitimized in order to make him eligible to inherit the French Throne. Later Catherine confronts Diane about her plans and threatens to tell Henry, since this would be considered treason and could lead to Diane and Bash's deaths. Though Diane tries to deny these accusations, Catherine tries to blackmail Diane by asking her to poison Kenna in exchange for her silence, or she gives another option: to leave French Court and never come back.
In For King and Country, Catherine tells Henry that Diane has been planning a treasonous action behind his back: to legitimize Bash, and erase their children from the line of succession.
Season Two Edit
In Banished, Diane de Poitiers returns to French Court after a lengthy absence. Catherine encounters Diane in the castle hall, and comments how daring it was of her to come back to court; however Diane counters with how the Queen banished her after Henry died and took away everything he gave her. Later the Queen learns from Bash the truth behind the deaths of her twins, and that it was Diane who left the nursery windows open and let the cold air come in and the babies froze to death. That night Catherine sneaks into Diane's chambers, and whacks her with a fireplace shovel; Catherine then murders Diane by strangling her, in revenge for killing her babies, stealing Henry from her, and for framing her daughter Claude.
- Historically Catherine and Diane were cousins in real life: They were both descended from the same Noble French House.
- This has never been mentioned on the show.
- Diane became involved with Henry about a year after he married Catherine.
- This was mentioned in A Chill in the Air
- Catherine thinks of Diane as a "Parasite"
- She said this in For King and Country
- Catherine blackmailed Diane, by threatening to tell Henry about her plans to have Bash legitimized.
- This occurred in Fated
- Diane left the castle because of this
- Catherine tried to get rid of Diane by revealing her Pagan practices to Henry
- This occurred in Inquisition
- Historically when Henry died, Queen Catherine not only forbade Diane from entering Henry's room; she also made her leave French Court, and return all the gifts Henry gave her.
- This was shown in Banished when Diane and Catherine met again.
- Historically when Catherine contracted scarlet fever, Diane nursed her back to health.
- Historically, Catherine regarded Diane as an intrusive older cousin.
- Historically, Diane encouraged Henry to sleep with Catherine so they could have children.
- Catherine is responsible for Diane's death in Banished.
- She did this after discovering that the deaths of her infant twins was the handiwork of Diane, who left the nursery windows open so the babies would freeze to death. Catherine learned the truth from Bash after he saved her life.
- Diane did this because of her intense jealously which came when she learned Queen Catherine was pregnant. Diane's feelings quickly rose to anger and intense hatred after the twins were born.
- Diane also said that she wanted Henry and Catherine to suffer and by killing their babies she ensured that they would.
- No one knows that Catherine murdered Diane, because Bash forced his mother away from French Court forbidding her to ever return...so it's assumed that she is elsewhere.
- In Safe Passage, Bash learns that Catherine murdered his mother.
- He tries to kill her because of this.