Bangor Synagogue was last located in the Tabernacl church, Garth Road
Research at Bangor University has discovered that Jewish people first settled in north Wales during the building of Edward I's castles.
Now Dr Nathan Abrams and Dr Sally Baker have put together a touring exhibition of their findings, celebrating Jewish history across the region.
Previous studies have focused on 19th and 20th century Jewish communities, but there is evidence that Jewish families settled in fortified towns like Caernarfon and Beaumaris back in the 13th century.
I think because Jews were mainly used for financing at that period, they were there to assist with the castle-building programme, said Dr Abrams.
In 1290, the Jews were expelled from England, and a little earlier from Wales. This was right at the height of the building work.
Maenofferen Centre, Blaenau Ffestiniog, 15 to 18 September
Main Arts Building, Bangor University, 16 to 30 October
Neuadd Dwyfor, Pwllheli, 6 to 20 November
"So I think once they'd fleeced them, they expelled the Jews and their properties were appropriated.
The exhibition, funded by a £19,000 grant from Beacon for Wales, then looks at the next influx of Jews to Britain from Eastern Europe, in the late 1800s.
Dr Abrams said: They travelled out from places like Liverpool into the Welsh countryside as peddlers.
But eventually they set up communities first in Bangor, then in Llandudno, Colwyn Bay, Rhyl and Wrexham.
Those peddlers moved on to renting small shops, and then owning large stores like Pollecoff's of Pwllheli and Wartskis of Bangor and Llandudno, which boasted of being 'By Royal Appointment.
Isidore Wartski went on to become mayor of Bangor, believed to be the first Jewish mayor in Wales.
More Jews again left Liverpool for north Wales during World War II, and the exhibition will include a recording of one mans memories of this period.
Wartskis of Llandudno had a branch in London's Bond Street
Since the mid-20th century, the Jewish communities have dwindled. There is no longer a synagogue in Bangor, though there is still a small one in Llandudno run by Jews from Manchesters orthodox community.
If you buy the Orthodox Jewish papers, youll find Jewish services going on all over north Wales during the summer, said Dr Abrams.
But as a practising Jew himself, he often returns home to London for religious holidays because the local community is so small.
The older members of the community died and the younger ones moved away to marry or go to university, he explained.
Dr Abrams would like to hear from anyone with further information on the Jewish diaspora in Wales.
He will also be assisting Gwynedd Archives staff at a free workshop on researching local and Jewish history at the Record Office, Caernarfon, 7pm to 8.30pm, on Tuesday, 21 September.