The site through which my research is currently focused is Catholic Hierarchy. It lists Bishops, past and present.
As I mentioned in my post about Ernesta in October 2009, we don't know her mother's maiden name. There were no Bishops with the surname Bergamasco, so the uncle must either be her mother's brother or a great-uncle.
So I am currently using the process-of-elimination method of research. First, I am looking for Bishops born between 1800 and 1860, which would be the most likely time frame for Ernesta's uncle to have been born.
Ernesta was born in 1874, so I can't imagine her mother was born any earlier than 1830 or any later than 1860. An uncle, if a brother to her mother, would probably have been born in the same time frame.
Bishops in Italy
Also, I am focused on Bishops who served in Italy, since that is what the family memoir tells us.
I am creating a Word file where I am storing information on each Bishop who fits this profile (born between 1800 and 1860; served in Italy). From there, I will do my best to locate information on each man and try to eliminate the possibilities.
Later, I may have to expand my search to other countries or another generation (if it turns out we are talking about a great-uncle versus an uncle; that would open up 2 more surname possibilities, at least, as then we would be looking at a man who was either Ernesta's mother's maternal OR paternal uncle, or Ernesta's father's maternal uncle).
One thing at a time.