Pedro León Díaz Gallo was an Argentine

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 statesman and priest. He was a representative to the Congress of Tucumán

Congress of Tucumán

The Congress of Tucumán was the representative assembly, initially meeting in Tucumán, that declared the independence of the United Provinces of South America on July 9, 1816, from the Spanish Empire....

 which on 9 July 1816 declared the Independence of Argentina

Argentine Declaration of Independence

What today is commonly referred as the Independence of Argentina was declared on July 9, 1816 by the Congress of Tucumán. In reality, the congressmen that were assembled in Tucumán declared the independence of the United Provinces of South America, which is still today one of the legal names of the...

.

Gallo was born in Santiago del Estero

Santiago del Estero

Santiago del Estero is the capital of Santiago del Estero Province in northern Argentina. It has a population of 244,733 inhabitants, making it the twelfth largest city in the country, with a surface area of 2,116 km². It lies on the Dulce River and on National Route 9, at a distance of...

 and studied at the Monserrat School in Córdoba

Córdoba, Argentina

Córdoba is a city located near the geographical center of Argentina, in the foothills of the Sierras Chicas on the Suquía River, about northwest of Buenos Aires. It is the capital of Córdoba Province. Córdoba is the second-largest city in Argentina after the federal capital Buenos Aires, with...

 until he was ordained, graduating as a teacher of art (or philosophy according to other sources) at the University of San Carlos.

Gallo was elected to represent Santiago del Estero in the Tucumán Congress and served for the declaration in 1816. He was vice-president of the Congress in August 1816 and twice president after it was moved to Buenos Aires

Buenos Aires

Buenos Aires is the capital and largest city of Argentina, and the second-largest metropolitan area in South America, after São Paulo. It is located on the western shore of the estuary of the Río de la Plata, on the southeastern coast of the South American continent...

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When the Congress was dissolved in 1820, he and his colleagues were imprisoned as traitors.

Gallo returned to Santiago del Estero and was a signatory of the peace treaty of Vinará in 1821, signing on his province's behalf with Pedro Miguel Aráoz

Pedro Miguel Aráoz

Pedro Miguel Aráoz was an Argentine statesman and priest. He was a representative to the Congress of Tucumán which on 9 July 1816 declared the Independence of Argentina....

 of Tucumán

Tucumán Province

Tucumán is the most densely populated, and the smallest by land area, of the provinces of Argentina. Located in the northwest of the country, the capital is San Miguel de Tucumán, often shortened to Tucumán. Neighboring provinces are, clockwise from the north: Salta, Santiago del Estero and...

 and José Andrés Pacheco de Melo

José Andrés Pacheco de Melo

José Andrés Pacheco de Melo was an Argentine statesman and priest. He was a representative to the Congress of Tucumán which on 9 July 1816 declared the Independence of Argentina....

 of Córdoba

Córdoba Province (Argentina)

Córdoba is a province of Argentina, located in the center of the country. Neighboring provinces are : Santiago del Estero, Santa Fe, Buenos Aires, La Pampa, San Luis, La Rioja and Catamarca...

. He was a minister in the government of Juan Felipe Ibarra, before retiring in Tucumán where he died.