[1] Born to a mestizo family, Morínigo pursued a military career, serving as a prominent officer of the Paraguayan Army during the Chaco War.

Morínigo gained fame in Paraguay during the February Revolution of 1936 by heading an expedition to the site of the Battle of Cerro Corá to retrieve the remains of Francisco Solano López.

After Estigarribia's unexpected death in an airplane crash on September 7, Morínigo was chosen by the army and Liberal ministers as interim President for the two-month period leading to new Presidential elections.

Soon afterward he announced a policy of "discipline, hierarchy and order" (disciplina, jerarquia, y orden) and stated that persons who spread subversive ideas would be "subject to confinement".

[4] On November 30, Morínigo banned all political parties and imposed a state of siege, which gave him the right to suspend civil liberties and arrest and detain people without trial.

In his self-coup and subsequent rule, he was greatly assisted by the 1940 Constitution, a severely authoritarian document written by Estigarribia a few months earlier that gave the president sweeping executive powers.

During his dictatorship he faced widespread resistance, including general strikes and military revolts, but he survived by maintaining the loyalty of the Paraguayan Army, which received 45% of the country's budget.

Morínigo relied on the right-wing Colorado faction Guión Rojo (the "Red Banner"), led by Juan Natalico Gonzalez, as a paramilitary police force to intimidate febreristas and Liberals.

At the same time, the United States sought to enhance its presence in the region and pursued close cooperation with Brazil, Argentina's traditional rival.

German immigrant schools, churches, hospitals, farmers' cooperatives, youth groups, and charitable societies became active Axis backers.

Nonetheless, Morínigo continued to maintain close relations with the heavily German-influenced Argentine military throughout the war and provided a haven for Axis spies and agents.

Despite the fact that 80% of soldiers and 90% of officers were against him, Morínigo had the backing of Colorado party militias and Argentinian President Juan Peron; he managed to win a conflict that caused many thousand deaths and up to 300,000 people to flee as refugees.

Suspecting that Morínigo intended to use this as a means to retain power, on June 3 some Colorado Party loyalists under Felipe Molas López revolted and sent him into exile in Argentina.

Supreme Court Chief Justice Juan Manuel Frutos was sworn in as interim president, serving the last two months of Morínigo's term until González was officially inaugurated on August 15, 1948.