Carlos Viegas de Gago Coutinho was born in Lisbon, in 1869. He joined the Naval Academy in 1886, standing out for his poise and intelligence. From a very young age, he was interested in the study of warships, namely wireless telegraphy, artillery, naval construction, magnetism, technical navigation problems in general.
From 1898 onwards, Gago Coutinho began his activity as a geographer. His works in this field, where he put into practice all his knowledge of geodesy, astronomy and mathematical geography, are among the most scientifically valuable works produced by the Portuguese in Asia and Africa. One of his most emblematic campaigns took place on the islands of São Tomé. Traditionally, cartography indicated that the Equator passed between the island of São Tomé and the islet then known as Ilhéu das Rolas. Then Commander Gago Coutinho proved that this line cut through the islet, a discovery that went down in history as a scientific milestone in the field of geodesy. So much so that, on 16 June 1923, the Government of São Tomé and Príncipe published an Executive Order recognising the discovery and naming the islet after Gago Coutinho.
In 1922, he undertook the first aerial crossing of the South Atlantic with Commander Sacadura Cabral, whom he had met in Mozambique. This milestone in the history of Portugal and the World was achieved thanks to Gago Coutinho's inventions - an adaptation of the sextant (instrument used by maritime navigators) and a course corrector -, which contributed greatly to the success of the voyage in terms of air navigation and whose concepts are still used today in the construction of cutting-edge instruments.
In the last phase of his life, Gago Coutinho dedicated himself to Nautical History, specifically to the period of the Discoveries. He made a remarkable contribution for the clarification of technical matters related to navigation in the 15th and 16th centuries, and Jaime Cortesão stated that Gago Coutinho was the introducer of the nautical-geographical method in the analysis of the History of Navigation.
By decision of the National Assembly, Gago Coutinho was promoted to Admiral in 1958, and died on 18 February 1959, one day after his 90th birthday. Without ever ceasing to dedicate himself to his research work, and at no time forgetting those who helped him in his achievements:
'And they blindly obeyed me, though we did not assert ourselves by the shine of our uniforms or swords, nor by the soldiers' bayonets. I did have weapons, but they were in their hands. We were not respected for our strength, but for the prestige of our persistent work, symbolised by the peaceful compass we carried in our hands'.