Real identity?
 

Which princess, which visits the monastery, and when?

Very interesting:
...

A simpler answer is possible?

In rabotenad picture Vasily Surikov used watercolor edyud " Skorn nun " (now in the Tretyakov Gallery ), written in Starocherkassom convent during a trip to the Don in 1893 , and for the princess and a nun posing Natalia Konchalovskaya - granddaughter of the artist.
The story itself , I think, is not tied to a specific historical event and specific real person.

Us-tin,

Looked and listened.
Thanks a lot.

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In the XVI century, Tsar Ivan the Terrible (1547-1584), Fyodor I Ivanovich (1584-1598), Boris Godunov (1598-1605).
How many of them in the picture?

In the XVI century, Tsar Ivan the Terrible (1547-1584), Fyodor I Ivanovich (1584-1598), Boris Godunov (1598-1605).
How many of them in the picture?

In all likelihood all, and no one in particular , because everything in the name of the picture. " King. 16th century ." There is no reference to konretnomu historical person , and shows the general atmosphere of the king out , meeting lyudom it simple .