Could someone provide me a history of Ald-Cyrod before all these slave rebellions? I'm mainly interested in lore of the Ayleids, but wouldn't mind information about human tribes before they were enslaved.

As you might expect, Cyrodiil isn't well documented before the Slave Rebellion.

As far as Ayleids go, there is some mention of how the Ayleidic empire became isolated from their Aldmer ancestors during the Merethic era in http://uesp.net/wiki/Lore:Before_the_Ages_of_Man:

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It sounds as if the beginning of the Camoran Dynasty is closely related to White Gold's independence. Certainly some Ayleids fled to Valenwood after the Slave Rebellions, so there may have been agreement between the Aldmer empires of Valenwood and Cyrodiil.

In thehttp://www.imperial-library.info/content/nu-mantia-intercept, Nu-Hatta describes the purpose of White-Gold Tower when it was originally built:

It's not obvious whether there was any human history in Cyrodiil before their enslavement - certainly this lies a long way back in the Merethic era. One note we have of those early human tribes is in the http://uesp.net/wiki/Lore:The_Adabal-a: