I just discovered that*, in 1554, when the Russians finally conquered the city, they put a weak Khan on the throne, in order to control the place. Two years later Ivan The Terrible annexed it after a rebellion, a Crimean invasion and stuff like that. The thing is, why would they put a "fake" Khan there instead of giving Astrakhan to a neighbouring noble? Vassalising Astrakhan was a smart move, but I really don't get why they thought a Khan would do a better job than say, a duke.
Was there a will to annex slowly? I can't find no proof anywhere of Ivan the Terrible beeing compassionate enough to accept another culture in his land, with another kind of leadership...
- The source beeing : https://en.wikipedia.org/wiki/Dervish_Ali_Astrakhani and the french Page of Astrakhan https://fr.wikipedia.org/wiki/Astrakhan (Weirdly they talk differently of the event between English and French)