EMBARGO (a Spanish word meaning "stoppage"), in international law, the detention by a state of vessels within its ports as a measure of public, as distinguished from private, utility. In practice it serves as a mode of coercing a weaker state. In the middle ages war, being regarded as a complete rupture between belligerent states, operated as a suspension of all respect for the person and property of private citizens; an article of Magna Carta (1215) provided that "... if there shall be found any such merchants in our land in the beginning of a war, they shall be attached, without damage to their bodies or goods, until it may be known unto us, or our Chief Justiciary, how our merchants are treated who happen to be in the country which is at war with us; and if ours be safe there, theirs shall be safe in our lands" (art. 48).
Embargoes in anticipation of war have long since fallen into disuse, and it is now customary on the outbreak of war for the belligerents even to grant a respite to the enemy's trading vessels to leave their ports at the outbreak of war, so that neither ship nor cargo is any longer exposed to embargo. This has been confirmed in one of the Hague Conventions of 1907 (convention relative to the status of enemy merchant ships at the outbreak of hostilities, Oct. 18, 1907), which provides that "when a merchant ship belonging to one of the belligerent powers is at the commencement of hostilities in an enemy port, it is desirable that it should be allowed to depart freely, either immediately, or after a reasonable number of days of grace, and to proceed, after being furnished with a pass, direct to its port of destination, or any other port indicated" (art. 1). The next article of the same convention limits the option apparently granted by the use of the word "desirable," providing that "a merchant ship unable, owing to circumstances of force majeure, to leave the enemy port within the period contemplated (in the previous article), or which was not allowed to leave, cannot be confiscated. The belligerent may only detain it, without compensation, but subject to the obligation of restoring it after the war, or requisition it on payment of compensation" (art. 2).
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)