Paul Concus posted as follows:

"Is it generally the case that in Cyrillic documents the name Gersh
appears as the equivalent of the Hebrew name Tzvi? (presumably because
one can't write Hersh, the actual Yiddish equivalent -- no H in Cyrillic?)."

Gersh was written in archival documents instead of the name Hersh for the
reason Paul gave. However, Yiddish names Gersh/Hersh were not
"equivalents" of the Hebrew name Tsvi.

The Yiddish name Hersh (= Gersh) is a kinui (a technical term defined by
rabbis in Europe) of the Hebrew name Tsvi. This means that if a man had
both of these names, he would be called to the Tora in an aliya in a shul
by the name "Tsvi Hersh ben Ploni" (where Ploni means the name of his
father). And if he were to seek a divorce >from his wife, his name would
have to be written in the Get (Divorce contract) "Tsvi haMechune Hersh",
where HaMechune means "alias" or "known as".

This is in accord with Jewish law in Europe, as set by the rabbis of
various countries, like Poland, for one. Getting identifying names right
for Jews seeking a divorce was an extremely important task because (if
wrong) of the possibility that the Get might later be declared to be
invalid, and therefor any future children of either man or woman might be
declared to be bastards under Jewish law.

In addition to the Yiddish name Hersh, other kinuim used in the same way
were Hershl, Hirsh, and Hirts.

A number of variants for both names Tsvi and Hersh can be seen by visiting
the JewishGen Given Names Data Base for Poland, at the web site:

< http://www.jewishgen.org/databases/GivenNames/ >

and searching for the name Tsvi using Global Text Search. These additional
names might appear in other archival documents.

Shabbat shalom,

Prof. G. L. Esterson, Ra'anana, Israel