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The Free Sea

1609 · by Hugo Grotius

Published anonymously at the request of the Dutch East India Company, originally a chapter of a larger manuscript on prize law: the sea cannot be owned, and navigation and trade are open to all peoples, against Portuguese claims to a monopoly of the route to the East Indies.

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Introduction

Grotius published “Mare liberum” anonymously in Leiden in 1609 at the request of the Dutch East India Company. It was originally chapter 12 of a longer manuscript, written from 1604, defending the company’s seizure of the Portuguese carrack Santa Catarina; the full manuscript was discovered only in 1864 and published as “De iure praedae”. The tract argues that the sea, like the air, cannot be occupied and is therefore free to all peoples for navigation and trade, so that Portugal’s claim to a monopoly of the route to the East Indies was void. It provoked replies from England (John Selden’s “Mare clausum”, 1635) and Portugal and became a classic of the law of the sea.

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