Katerina (Katherine) first met Rebekah in 1490 after she was banished to England by her parents to live with relatives for having a child out of wedlock. Rebekah was living as a noblewoman with her brother, Klaus and Elijah, in England at the time. Rebekah and Katerina met at a fancy party, and Rebekah quickly realized that Katerina was the Petrova doppelgänger they been waiting for, for almost five hundred years. Rebekah then became close friends with Katerina, and introduced her to Klaus and Elijah, who began courting her in order to trick her. When Katerina learned that she was to be sacrificed in order to break the curse binding Klaus' werewolf heritage, she escaped with the help of several of the Mikaelsons' associates, Trevor and Rose, and then tricked Rose into giving her vampire blood, so she could transition. Once Katerina was a vampire, her blood could no longer be used for the ritual as it had to be human blood; she then ran away, fleeing the wrath of Klaus. This act destroyed Klaus and Elijah's bond as brothers for centuries as Katerine pushed her way between the two brothers, and Rebekah began held a grudge against Katerina ever since.