The Empire of Brazil remained the only monarchical nation in South America in the 20th century, after a military coup failed to ensure a republic in November 15, 1889. The leaders of the coup, chiefly Benjamin Constant and Lopes Trovão, were arrested and sentenced to life prison. The commander of the Army, Marshal Deodoro da Fonseca (a staunch monarchist), instead of proclaiming the Republic was convinced to take the post of Chairman of Council of Ministers (head of Government, prime minister). He would resign the following year and was replaced by Rui Barbosa, a brilliant orator and diplomat, and a moderate republican turned loyalist.