Board Thread:Lore Discussion/@comment-114.124.235.53-20180629193459/@comment-23.121.236.132-20180725041314

http://elderscrolls.wikia.com/wiki/Dragon_War

Hopefully the background provided here will help. In summary, the Dragon War took place after Atmoran people came to skyrim. The Atmoran's created the dragon cult and those ancient nords were the ones enslaved by Alduin. So the events following the Night of Tears and Ysgramor's reconquest of Skyrim preceed the Dragon War.