Why did Peter the Great change his daughters' title to Tsesarevna?

Question

Having won the Great Northern War in 1721, Peter the Great promoted himself from Tsar to Emperor. At the same time, he seems to have changed the title used by his daughters from Tsarevna to Tsesarevna. (By symmetry, it seems that he would have changed the title used by any son of his from Tsarevich to Tsesarevich, although by this point he had already had his last surviving son, Alexei, tortured to death.) What was his rationale for doing this?

My own best guess is that the change in his daughters' titles reflected the change in his own title; Tsarevna meant something like royal princess, whereas Tsesarevna meant something like imperial princess, at least in Peter's mind. According to this theory, the Tsesar- corresponds to the English/Latin Caesar, i.e. Emperor, and the -evna suffix, of course, means daughter. However, I can see two problems with this point of view:

1. The word Tsar is itself derived from the title of Caesar.
2. The Russian transliteration of Caesar is Цезарь, whereas the Russian spelling of Tsesarevna is Цесаревна; note that the former uses the letter з where the latter uses the letter с.

Can anyone shed any light on this?

Answer 1

When Peter 'upgraded' the Russian title of 'tsar' (царь) to 'emperor' (император), this meant that the corresponding titles would have to be given a similar jump upwards.

The specific issue arose because the Westernized 'emperor', though sharing its root with the Slavonized 'tsar' in the Latin 'caesar', was a more important title than that of tsar, the two not being synonymous. In the previously used 'tsarevich' the suffix '-vich' ('-евич') indicates 'son of'—hence, the meaning of the title is 'son of tsar'.

Therefore, 'tsarevich' (царе́вич) or 'son of tsar' was unsuitable for someone who was the son of an emperor. Hence, 'tsesarevich' (цесаре́вич) or 'son of emperor' was created to remedy that problem. The female variant 'tsarevna' (царевна) was similarly unsuitable for 'daughter of emperor' for which the more apt 'tsesarevna' (цесаре́вна) was created. Their meanings in translation, in this case, are less important than the words in Russian which express a filial relationship towards the ruler because the translations are a matter of convention.

A similar translation problem arises with 'velikiy knyaz' which can be rendered as 'Grand Prince' or 'Grand Duke'—both being correct—which could also be accorded to the scions of the imperial house.

Answer 2

What was his rationale for doing this?

Seems like a simple Westernization of Russian official vocabulary, which was a mainstream policy of Peter I. This was a message to the European leaders about the emerging Russian power and its global ambitions, so it was phrased in terms well understood in the West. I doubt that "Tsesar" communicates any greater status than "Tsar", it simply speaks to Western ears.