Immediately after Palpatine's death Grand Vizier Sate Pestage takes control of the Empire. However, he lacked the charisma, Force powers, and terrifying presence that both Emperor Palpatine and Darth Vader used to keep the Empire together. The Empire soon fragmented and power was devolved to a handful of self appointed warlords throughout the Empire's former territories. The first of these warlords was Admiral Blitzer Harrsk. [spoiler]Palpatine was able to transfer his consciousness into the Force before he died at the battle of Endor. He spent a number of years as a non-corporeal Force entiry until he was finally able to transfer his consciousness into a cloned body of his younger self that he had prepared some years prior - the man knows how to plan ahead.[/spoiler]

You have everything correct except for the new imperial leader. The new leader was Grand Admiral Thrawn

Thrawn came in after Blitzer but yeah, can't believe I skipped him. Man's like my favourite EU character. *hangs head in shame*

Oh shoot I forgot about the earlier guys. I was thinking him because he was the longest top ranking guy (as far as I know)

Thrawn is da man! :) I'm still mortified by how Disney scrapped anything and everything to do with the Expanded Universe. I mean how cool would a stand alone Admiral Thrawn movie be? Or for characters like Mara Jade, Kyle Katarn, Corran Horn, etc to make appearances. I really hope they haven't made Luke just another celibate monk like the prequel Jedi. I haven't heard any mention of Mara Jade or even of him having a wife in the new movie :(