The War of the Eagle and Lion was a rebellion against the Adrestian Empire by the nobility of the northern region of Faerghus that occurred from Imperial Year 747 to 751. The conflict was sparked by Loog of House Blaiddyd, a direct descendant of the hero Blaiddyd who fought in the War of Heroes. Aided by the mysterious tactician Pan and his sworn friend Kyphon, the scion of House Fraldarius, Loog rallied the nobles of Faerghus to claim their independence from the Empire.
The fighting lasted for four years, until Loog's forces triumphed decisively over the Emperor's army at the Tailtean Plains. During the ensuing armistice, Loog's faction negotiated peace terms with the Empire and the Church of Seiros, with House Charon serving as mediator. The negotiations concluded with the Empire and the Church acceding to Faerghus's independence. On the 21st of the Red Wolf Moon, the Holy Kingdom of Faerghus was formally founded, and the Church crowned Loog, the King of Lions, as the fledgling nation's first monarch.
A damaged book in the Shadow Library of Abyss titled "Burnt Remnants of a Report" implies that Loog's victory in the War of the Eagle and Lion was achieved in large part due to soldiers and powerful weapons supplied by Those Who Slither in the Dark, as Pan was not merely a masterful tactician, but one of their members.