Complex sentence: Marco Barbaro (1511--1570) was of the Venetian noble Barbaro family and the author of several writings of which his "Genealogie Patrizie," that outlined the geneaology of the various noble families of the Republic of Venice, is his most famous.
Split into simpler sentences: Marco Barbaro (1511--1570) was of the Venetian noble Barbaro family. His "Genealogie Patrizie," that outlined the geneaology of the various noble families of the Republic of Venice, is his most famous.