In 1903, he was able to convince the American government that the Isle of Pines had been part of the Cuban territory since 1511, and on March 2, 1904, he signed the Hay-Quesada Treaty.
In 1903, he successfully argued to the American government that the Isle of Pines had been a part of Cuban territory since 1511, leading to the signing of the Hay-Quesada Treaty on March 2, 1904.