João de Castro
Portuguese explorer
Dom João de Castro (27 February 1500 – 6 June 1548) was a Portuguese nobleman, scientist, writer and colonial administrator, who served as the fourth Portuguese Viceroy of India from 1545 to 1548. He was called Strong Castro (Portuguese: Castro Forte) by the poet Luís de Camões. De Castro was the second son of Álvaro de Castro, the civil governor of Lisbon. His wife was Leonor Coutinho.
Early life
As the younger son of Álvaro de Castro, João was destined for the church. He studied mathematics under Pedro Nunes, along with Luis, Duke of Beja, son of King Manuel I of Portugal, with whom he formed a lifelong friendship. At eighteen, he went to Tangier for several years, where he was knighted by Dom Duarte de Menezes, the governor.
Voyages to India and the expedition to Egypt
In 1535 de Castro accompanied Dom Luís to the siege of Tunis, where he refused knighthood and rewards from Emperor Charles V. When de Castro returned to Lisbon, the king awarded him the commendation of São Paulo de Salvaterra in the Order of Christ in 1538.
Soon after, de Castro left for India with his uncle Garcia de Noronha, and participated in the relief of Diu upon his arrival at Goa. In 1540 he served on an expedition to Suez under Estêvão da Gama (the son of Vasco da Gama and then viceroy of India), who knighted his son, Álvaro de Castro in recognition of D. João.
The public source identifies “João de Castro” as portuguese explorer. This brief keeps that definition visible, then builds a research path around João, Castro and Portuguese.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Aug 9, 2026. The linked authority identifier is Q1352529. VIAF identifies the subject as 39545104. The Library of Congress control number is n85029903. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1500, 1548, 1545 and 1535.
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This entry incorporates text from “João de Castro” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.