When France's first culture minister, André Malraux, stepped in in 1965 to preserve the elegant 15th-to-18th-century architecture of the Marais, the dilapidated neighborhood was on the brink of being bulldozed by property developers.
But at least one of its celebrated mansions, the Hôtel des Ambassadeurs de Hollande, had already found its savior in the colorful figure of Paul-Louis Weiller.
Mr. Weiller was a World War I French aviation hero, founder of several airlines that eventually became Air France and successful industrialist and financier. He also had a passion for rare books and real estate. The mansion, a sumptuous but deteriorating, architectural gem listed as a national landmark in 1924, proved to be irresistible.
He bought it in 1951 and, with the advice of Gerald Van der Kemp, chief curator of the Château de Versailles, set about its restoration.
