I recently read about the new law in Spain that will offer citizenship to anyone who can prove Sephardic Jewish ancestry. However, in my attempt to find out how to apply for citizenship with regards to this new law, I'm having difficulty finding concrete information. I believe my case is very straightforward, as my grandfather and his family (who were all Sephardim) emigrated to New York from the Ottoman Empire in the early 1900s. They lived in a tenement building that is now a museum (Lower East Side Tenement Museum), and information about their specific apartment and the family's history readily acknowledges that they were all Sephardic, and in fact even discusses the family's struggles as a minority in the mostly Ashkenazic Jewish community living in New York at the time. I am not a practicing Jew, though I read that is not a requirement to apply for citizenship under these new guidelines.

However, I am struggling to find out how exactly to begin the application process and what documents I will need. I read somewhere that you must get a rabbi or a Jewish organization to certify your Sephardic ancestry, but given that my grandfather's Sephardic status is well-documented in a museum, would my case be less complicated to deal with? Would proving my Sephardic ancestry be as simple as proving my relation to my grandfather?