Jörðgarð Book 5 - The Northwest Volume 2: Ása: The Ruins of the Fallen Æsir Empire

From the introduction:

In terms of the Æsir Empire, postwar means a number of things. Before the final battle, it already meant a mostly empty land. By the time that the Hárdraugur (High Draug) Martröð met his end, the women and children had fled, some eastward, to Miðgarð and the last Æsir refuge, ruled by the fey King-God Óðinn, most southward into Vétrnývlast to integrate themselves with the Slovánski there. The latter also were of Æsir lineage, having migrated out of the empire at an earlier time. Most of the Æsir men had gone to war. More than a million died. A few of them still survive.