I know that when i first came here this is what i was looking for, so I assume a bunch of other people might want this too. This code requires you to have the character that you wish to modify selected, as well.
This is a list of the various ancillaries (retinue members) that can be added with the giveancillary command. Giving Ancillaries and Traits to Apies/Assassins As mentioned above, enter the console with the key. Medieval 2 Total War Traits And Ancillaries List Of Words.