Michel David-Weill United Lazard’s Finance Empire

Michel David-Weill, the long-serving patriarch of the New York and Paris houses of the Lazard banking dynasty, expanded the investment boutique led by his forebears and knitted it more closely to its sister business in London.

The Frenchman was credited with reviving the bank’s uncertain fortunes after he took over in 1977—modernizing the storied franchise and globalizing its operations. Under Mr. David-Weill, the bank traded on its mystique as a discreet, family-owned counselor to some of the world’s biggest companies.