Dragon Priest Empire
The Dragon Priest Empire grew out of the Dragon Priest religious movement, which was founded by Sh'kial and greatly expanded under Dzree beginning in 205 BV. The empire conqurered Shard during Corik's reign, but eventually crumbled following Dzree's death in 1 BV.
The Elanthian Timeline provides an account of major events during the approximately 200 year rule of the Dragon Priests.
Dragon Priest Revivals
Over time, various groups have attempted to revive the Dragon Priest empire. Some notable examples:
Around the time of the re-founding of the Bard's guild in Crossings, Siryn and Silvyrfrost were attacked by members of a renewed Dragon Priest organization.
More recently, Hhrsaraa has claimed to be the Empress of the Dragon Priest Empire. Further, she claimed to be part of Dzree's lineage.