In connection with an earlier posting about the “Hellenists” mentioned in the book of Acts, I mention the “Theodotus Inscription,” a Greek dedicatory inscription (lst century CE) from Jerusalem, which clearly reflects the movement of Greek-speaking Jews from the Diaspora to Jerusalem. These are likely the sort of people designated the “Hellenists” in Acts 6–7. For more information on the inscription go to online sites here and/or here.
Of course, this doesn’t settle by any means questions about the historicity of details about “Hellenists” in Acts. But it does show that there were Greek-speaking Jews in Jerusalem in the time in view. Note also the reference to the “synagogue of the freedmen” in Acts 6:9, who are portrayed as tackling Stephen, likely Jews manumitted from slavery in Diaspora locations who had relocated in Jerusalem.