The Berserker Wars - Fred Saberhagen

With the support of the peace loving Carmpan Race, earth descended humanity continues to lead the struggle in the ongoing thousand-year war against the Berserkers, an unliving, self-replicating enemy programmed to destroy all life.
Almost all the information earth descended humanity have ever had directly from the Carmpan on any subject—Berserkers, the Builders, the Carmpan themselves, the Elder Races, almost everything—a very great proportion of this information has come to our Solarian worlds through long-distance communications signed by one individual, known only as Third Historian.
Here are eleven of THs translated communications along with an explanation of their discovery by Archivist Ingli:
Stone Place, The Face Of The Deep, What T and I did?, Mr. Jester, The Winged Helmet, Starsong, Some Events at the Templar Radiant, Wings out of Shadow, The Smile, The Adventure of the Metal Murderer, and Patron of the Arts.