Date Created: 18 April 2016
If this photo was taken in 1890 that means that Khan of Khiva (Khoresm) in that time was Muhammad Rakhim-khan II (1845—1910) — the 11th ruler from Uzbek dynasty of Kungrats in Khivan khandom with years of his ruling 1864—1910.
More details about him are in Russian in Wikipedia:
Author: Poul Nadar (1820-1910)
Owner: French photographer Poul Nadar (1820-1910)
Location: Khiva, Uzbekistan
Link to Website: http://yvision.kz/post/527572