Kyrian revisionist history
Revisionist history was the practice of re-writing one's own history in order to support the narrative one wished to convey.
Klingons practiced revisionist history when it benefited the Klingon Empire.
According to Jadzia Dax, tasked with telling the saga of Sirella's maternal line, "when Emperor Reclaw was killed, all the members of the Imperial Family were also put to death. Including Shenara. When the Third Dynasty was founded ten years later, a new group of Klingons were given the titles and the names of the original Imperial Family to create the illusion of an unbroken line. So the woman that you think of as your twenty third maternal grandmother isn't related to you at all. Your real ancestor's name was Karana, a concubine living outside the Imperial Stables." She agreed to let the matter lie when Sirella objected. (DS9: "You Are Cordially Invited")
In 2368, Gowron rewrote Klingon history by claiming that it was his courage and genius which brought an end to the Klingon Civil War, and omitted all mention of the Federation's help in his rise to power. (TNG: "Unification I")
Around 3074, after viewing The Voyager Encounter at the Museum of Kyrian Heritage, a backup of The Doctor criticized the Kyrians for portraying themselves as martyrs, heroes, and saviors, while portraying the crew of USS Voyager as the villains in an encounter with the ship seven hundred years earlier. He suggested that their motivation was to make themselves feel morally superior, adding, "Revisionist history. It's such a comfort." (VOY: "Living Witness")