"So for anyone with Irish Jewish ancestry - and there are thousands worldwide - a wealth of information awaits."
Mr Rosenblatt heads the Irish Jewish Genealogical Society, a division of Dublin's Irish Jewish Museum. The project stemmed from his efforts to trace his own roots.
"I was researching my family tree and I discovered that my grandmother wasn't my grandmother at all [they were not even related].
"And I also found records about the Jewish community that others would not know existed. It's became a compulsive hobby.
"Over the past 20 years, Jewish communities around the world have become increasingly interested in their European ancestry, with many visiting the lands once inhabited by thriving communities which had existed for many centuries.
"Although the Jewish presence in Great Britain is well documented and, therefore, largely accessible to researchers around the world, Ireland is a totally different story. It is only now being revealed in detail."
He considered "this enormous collection, spanning approximately three centuries and containing details of over 52,000 individual records, as not only an enduring testament to my community and our ancestors. It is more an archival memorial to their important contribution to our much loved adopted homeland."
His records have been called upon by the team of the hit TV series Who Do You Think You Are? on both sides of the Atlantic.
Actress and author Rashida Jones, the daughter of composer Quincy Jones, learned about her Jewish ancestors. "Dervla Kirwan, the actress, found her Hebrew origins through the records."
But Mr Rosenblatt is still trying to complete his own family search. "I am looking for anyone doing work on Zarnow in Poland as I am trying to find [details about] my grandmother there."
