The provided text discusses the historical background surrounding Boquerón Battle Victory Day in Paraguay, focusing on the Gran Chaco lowland plain shared by several South American nations. For decades, tensions simmered between Paraguay and Bolivia regarding territorial governance over this strategically vital geographic region. These geopolitical disputes intensified significantly due to rumors of abundant petroleum reserves hidden beneath the terrain. Consequently, powerful international petroleum corporations became involved in the conflict, with Royal Dutch Shell supporting Paraguay and Standard Oil backing Bolivia.