André Poniatowski

[1] His paternal grandparents were Prince Józef Michał Poniatowski, a prominent composer and a singer, and Countess Matilda Perotti.

[8] In pursuit of investment opportunities, Poniatowski went to San Francisco and formed a syndicate to rework old Gold Country mines using modern methods.

In addition to their railway, mining and power interests, Poniatowski and Crocker built Tanforan Racetrack near Sky Farm, his winter residence in Burlingame.

[8] During the Interwar and early World War II period, Poniatowski leaded the design of experimental infantry tank, SEAM G1P, which had reached the prototype stage, unlike the vehicles proposed by other contesters, however, without weapons and proper engine,[10] which then was captured by German forces.

[11][12] Together, they were the parents of at least five sons, including:[13] In June 1911, the Princess attended the coronation of King George V in London with her sister.