Why do Jews look like Caucasians?

I think you just made that up. Do you have a cite?

The genetics actually tell a different tale. The Y chromosome of Jewish men around the world is generally traceable to the Middle East, but the mtDNA (inhereted only thru the female line) tends to look like that of whatever local population the Jews are living in.

One other thing…you can always tell a Jew from a white man because of the Jew’s horns.

Was there a time when Judaism was a proselytizing religion? That might explain the additions to the gene pool. What i don’t understand is how the jews migrated to russia-was this before the year 1000? or after?

Primarily migration from Germany, Lithuania, and Poland. To a lesser extent, the Khazars.