He was a promoter of art, music, and literature in Monaco and served as the head of the country's delegation to the United Nations Educational, Scientific, and Cultural Organization (UNESCO) and to the International Olympic Committee.

[5] A veteran of World War I, Pierre had fraternized in artistic social circles in France, becoming a good friend of Marcel Proust and Jean Cocteau.

[6] She conducted a media operation to pivot the principality's reputation from that of an "interior" site of fancy gaming tables and midnight catering for wealthy adults to a family-oriented outdoors venue, offering roomy beachside cabanas, golfing, a circus and, in 1929, the first Monaco Grand Prix.

[6] While the increased tourist traffic swelled SBM's 1928 profits to 98 million French francs, it also drove up citizen and worker demand for reforms, which Louis II publicly decried, while delegating Pierre to meet with the leaders of the National Council, all of whose members resigned that year in protest.

[6] Infuriated by failure to obtain workplace improvements at SBM, on 24 March 1929 600 Monegasques stormed the palace, prompting Pierre to negotiate with them and present their demands for constitutional and labor reform to the monarch, who agreed to fresh elections and other concessions that forestalled revolution.

[7][15] One magazine story reported that "The union ended ... under circumstances which prompted the temperamental father-in-law to vow he would call out the Monégasque army if the prince ever set foot in the principality again.