sentences:  That purchase played a significant role in the ouster of Santa Anna by Mexican liberals, in what is known as the Revolution of Ayutla, since it was widely viewed as selling Mexico's patrimony.As the liberals made significant political changes in Mexico and a civil war broke out between conservative opponents to the liberal reform, the liberal government of Benito Juárez negotiated with the U.S. to enable the building of an interoceanic route in southern Mexico.A treaty was concluded in 1859 between Melchor Ocampo and the U.S. representative Robert Milligan McLane, giving their names to the McLane-Ocampo Treaty.