Secrecy

The Política de Sigilo and
the Erasure of Pêro da Covilhã

Beyond the obvious operational need for cover when spying on exiled traitors in Castile or disguised as a Muslim merchant in the ports of the Indian Ocean, Pêro da Covilhã’s legacy fell victim to a deliberate, state-sponsored intelligence blackout known to historians as the Política de Sigilo (Policy of Secrecy).

The Missing Decade (1488–1498)
and the Rivalry with Castile

Toward the end of King Dom João II’s reign—particularly during the ten-year window between 1488 (when Covilhã reached Calicut and Bartolomeu Dias rounded the Cape of Good Hope) and 1498 (when Vasco da Gama dropped anchor in India)—Lisbon clamped down on all geographical intelligence. The primary driver was geopolitical rivalry with Castile. With the Reyes Católicos (Ferdinand and Isabella) eager to reach the spice islands of the East after Columbus’s 1492 voyage, both Iberian crowns were locked in high-stakes diplomacy to divide the unexplored world into two spheres of influence, culminating in the Treaty of Tordesillas (1494).

Dynastic Erasure
Under King Dom Manuel I

Following the death of Dom João II in 1495, the crown passed to his cousin and brother-in-law, Dom Manuel I (“the Fortunate”). Under Manuel’s reign, the policy of secrecy took on a political dimension: it became a convenient instrument to aggrandize the new monarch’s reputation as the sole visionary behind Portugal’s eastern empire, at the expense of Dom João II. Expeditions prepared under João II—most notably Vasco da Gama’s—were celebrated as personal triumphs of Manuel’s reign, while covert missions commissioned by João II, such as Covilhã’s overland reconnaissance of the Indian Ocean, were quietly sidelined lest they detract from da Gama’s—and therefore Manuel’s—glory.

Did Covilhã’s 1490 Cairo Report Reach Lisbon? The Castanheda Clue

For centuries, historians debated whether the monumental intelligence report and annotated chart that Pêro da Covilhã entrusted to the royal courier José of Lamego (o Sapateiro) in Cairo in late 1490 ever reached King Dom João II in Lisbon.

As the Conde de Ficalho (1898) and historian Jaime Cortesão demonstrated, a telling discrepancy between the first and second editions of Fernão Lopes de Castanheda’s História do Descobrimento e Conquista da Índia pelos Portugueses provides virtual proof that the map arrived—and was later suppressed:

  • The 1551 First Edition:
    In the original 1551 printing of Book I (Chapter 1), Castanheda explicitly wrote that Covilhã dispatched José of Lamego to the King with letters and the navigational chart on which he had written the names of the ports of India and Sofala, noting parenthetically that the names were entered “ainda que mal escriptos” (“albeit poorly written”).
  • The 1554 Censored Edition:
    Just three years later, in the revised 1554 second edition of Book I, that entire detail vanished—replaced by a statement claiming it was impossible to know whether King João II ever received Covilhã’s report.

As Ficalho and Cortesão argued, no chronicler invents a specific, unglamorous physical detail like “albeit poorly written” out of thin air. That phrase could only come from someone who had examined Covilhã’s cramped field notations on the physical chart in the royal archives—before royal censors ordered the admission scrubbed from the 1554 edition.

Bla bla bla…

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