How does the author use flashback in the novel, Hardfought?

The flashbacks to the original Prufrax, from whom thousands of clones have been bred, explain how the war started and how the disastrous restriction to historical knowledge began among humans. The flashbacks tell how the Senexi start the war without intent by doing what they have always done; they cleanse a few planets of all life, including human colonists, as part of their seeding process. The genocidal attacks infuriate the humans, who retaliate by destroying Senexi ships. The original Prufrax has no doubts about which species has justice on its side, and her battles include one in which she destroys a Senexi processing plant that is grinding up the intelligent native species of a gas-giant planet. Such matters seem sure to further inflame the anger of humans, but the "overs" (probably political and military leaders) decide that they need to control access to history in order to manipulate people into fighting what may be a very long war.