Complex sentence: The Sursocks were part of an international bourgeoisie that circulated amidst the cities of Alexandria, Beirut, Cairo, Istanbul, Paris and Rome and ultimately became one of the "Seven Families" which defined Beirut's merchant nobility.
Split into simpler sentences: The Sursocks were readily admitted into Ottoman, Egyptian and European high societies and were part of an international bourgeoisie that circulated amid Alexandria, Beirut, Cairo, Istanbul, Paris and Rome. They ultimately became one of the "Seven Families" which defined Beirut's merchant nobility.