Born in Viana do Alentejo, on 4th April 1843, was the son of doctor António José de Sousa, who came to practice in Viana in that same year, and Maria José de Sousa.
He graduated in Agronomy and Veterinary Medicine in 1864, at the age of 21, at the Lisbon Agricultural Institute, with a thesis on agriculture in the municipality of Viana, published in the magazine Archivo Rural that same year.
He was close with several prominent figures of the time, at national level, but always refused the most important positions he was offered (professor at the Lisbon School of Veterinary Medicine, director-general of agriculture, deputy, civil governor) because of the dedication he had to the land where he was born.
He worked as intendant of livestock in Évora and Coimbra and as a district agronomist in Beja. After the 1870s, he co-founded the "Baixo Alentejo Farmers’ League" and was a member of the Royal Central Association of Portuguese Agriculture, where he organized the Agricultural Congress of 1888.
He created the "South Wine and Olive Union" in 1892 in Viana do Alentejo, which was one of the most daring projects of Alentejo’s society of the time and the first Portuguese agricultural cooperative. It is also thanks to António Isidoro de Sousa that the Industrial School Médico Sousa was created, in 1893, within the scope of action of the Union, whose designation honours his father.
He led the movement that fought for the restoration of independence of the municipality, lost to Évora in 1895, and finally recovered on 13^th January 1898. He was elected president of the new municipal council that same year, a position he only held for a year and didn’t agree to renew. However, this opportunity gave rise to the launch of a vast program of public works, particularly those within the supply of water and the plumbing for Viana’s fountains and “chafarizes”.
He travelled through Europe, getting to know the agricultural advances of the time, which he tried to implement in Viana. He promoted and planned the splitting of large estates, favouring access to the land to the most disadvantaged classes.
He encouraged the association of farmers and the cooperativism of the workers who, under his support, created in Viana the Caixa Económica Operária Isidoro, in 1899. This association provided mutual help in sickness and it even had a primary education class for members.
He brought to Viana Leite de Vasconcelos, a prominent archaeologist, to archaeological explorations. He started the horse races in Évora and Lisbon.
He passed away on 19^th December 1914, at the age of 71, due to cerebral haemorrhage.
A bust in his honour was inaugurated in 1940, in the República square.

REFERENCES
BAIÃO, Francisco, “Efemérides. 1914-2014-centenário da morte de António Isidoro de Sousa”, Boletim Municipal do Município de Viana do Alentejo, nº84, Dezembro de 2014, p. 27.
BAIÃO, Francisco, “Efemérides. 1914-2014-centenário da morte de António Isidoro de Sousa”, Boletim Municipal do Município de Viana do Alentejo, nº84, Dezembro de 2014, p. 27.
BANHA, Luís Miguel, ILARVS: Contributos para o estudo da olaria tradicional de Viana do Alentejo, Viana do Alentejo, Câmara Municipal de Viana do Alentejo, 2014.
SOUSA, João Manuel Santana de, História da Primeira Adega Social Portuguesa, Viana do Alentejo, Câmara Municipal, 1993.