Please help me find my roots

I am looking for information on my ancestors and lost relatives.
Unfortunately, I do not have a lot to go on since records and
information were lost in fear of persecution following the revolution.

I know that my great-great-great grandparents came to Odessa, Russia
from Berlin via Copenhagen possibly sometime in the 1840-60s. My
great-great-great grandfather (Julius Neumann) was an engineer and came
to Odessa to oversee railroad construction (perhaps this is a unique
attribute that could be used to track him down).

Bernd J. Kaup...

The surname NEUMANN is very widespread in Germany, even if you take for
granted that the last german hometown was Berlin.Presently there are
more than 3000 NEUMANN listed in the phone directory of Berlin.

snip

The best way is anyhow starting in the present times an then working back.

mfg
bjk

They had a daughter Alvina Neumann and a son names Julius Neumann
(Jr.), I am not sure where either of them was born or when.

Julius Neumann (the son) we believe was married to a French woman and
escaped to France during the revolution (they might have had a daughter
named Katie).

Alvina married Konstantin Speridonavich Borodin and they had at least
three children, one of which was Elena Konstantinovna Borodina born on
the 2nd(?) of May, 1888 who was my great-grandmother and lived at
Pirogovskaja Street #12. In 1910 she married Stepan Ivanovich Iluhin
(born in 1889) who was a banker in Odessa, they had three children one
of which was my maternal grandmother.

Like I said, I have little to go on and am not sure where to start, so
any help or advice from you is really appreciated.