I found out that Empress Yodit of Abyssinia had plans to restore Israel under her rule and abdicate the throne of Abyssinia to become Queen of Israel. She never could because of constant uprisings against having a Jewish Empress by the Coptics in Abyssinia.
But what if she'd quelled the rebellions long enough to assemble an army to return to Israel sometime between 960 and 980 AD? What would the campaign look like? How long would her new Israel last? Would there be any changes in the world today? I have a rough idea of a timeline, but I'd like some help if possible to make it really work out well.
EDIT: Yodit sought a "Kingdom of Greater Israel", that would include the historic homeland, as well as Sinai and Jordan since they were considered Jewish holy sites. She had plans for a later conquest of Damascus because it was another holy site, but if that happens, it'd be further down the line.