How should on proceed to track the roots if I only have (i) the name; Joseph Galindo or Joseph de Urrea, (ii)date of birth May 15th 1720, and (iii) place Zaragoza (no detail where in Zaragoza though.

Is it a needle in a heystack to search for church records (the online one do not provide inforamtion). How should one proceed?

Further, there is an old family story that he escaped Spain, changed his name from Marquis Joseph de Urrea to Joseph Galindo d'Urrea. Suprisingly, he married a french huguenot (Marie Pirou) in London in 1750.