Joao de Castro was born on 27th February 1500 in Lisbon, Portugal, and he died on 6th June 1548 (aged 48 years) in Goa, India. Joao was a Portuguese nobleman and naval officer who contributed to the science of navigation. He was also the first person to note that the compass needle deviated due to the magnetic effects. Joao spent 20 years in Africa where he was a part of the Seige of Tunis for which he was rewarded. But he refused both the knighthood and the rewards. He sailed for India afterwards. On landing in Goa he helped the Portuguese in the release of Fort Diu. After his return to Goa he served as the Fourth Viceroy of Portuguese India.
Do you know: Joao wrote three Pilot books which are considered remarkable for their scientific observations and contributed majorly to the study of seafaring.
