in international law, a state of preparedness declared by a neutral power or group of neutral powers to defend its maritime trade on the sea from belligerent countries with the aid of armed forces (for instance, having neutral commercial ships convoyed by warships).

Russia was the first to advance the principle of armed neutrality, on Feb. 28 (Mar. 11), 1780, during the struggle of England’s North American colonies for their independence. Russia addressed to England, France, and Spain a declaration in which the aim of Russian policy was proclaimed to be the defense of Russian trade and that of other neutral countries from the violent acts of the English fleet in this war. In the declaration, the following basic positions were put forward, and they later became principles of armed neutrality: (1) neutral states have the right to trade with belligerents and also the right to navigate freely along the shores of belligerent powers; (2) enemy property found on a neutral ship is inviolable and cannot be seized by belligerents if it is not military contraband; (3) cargoes are recognized as military contraband only if they are directly intended for the conduct of military operations (arms, ammunition); and (4) a port is considered to be blockaded by a belligerent country only when entry into it presents a clear and effective threat from the blockading state’s warships stationed nearby (this principle demands that there be an actual blockade, not a “paper” one). The North American states recognized these principles, as did France and Spain. England, while officially rejecting the principles of armed neutrality, was compelled to take them into consideration.

The policy of armed neutrality undermined England’s monopoly power at sea and objectively aided the American people’s struggle for independence. The declaration on armed neutrality demonstrated the increasing significance of Russia in international affairs.

Russia later established the 1780 principles of armed neutrality as the basis for treaties of alliance with Denmark (July 9, 1780), Prussia (May 8, 1781), Austria (Oct. 9, 1781), Portugal (July 13, 1782), and the Kingdom of the Two Sicilies (Feb. 10, 1783). In the 19th century, the principles of armed neutrality were extended and supplemented in the conclusion of the Russo-Prussian treaty (1800) on the formation of a so-called second armed neutrality for defense of neutral maritime trade; Denmark and Sweden also became parties to this treaty. England recognized these principles during the conclusion of the Declaration of Paris of Apr. 16, 1856, on war at sea.

Subsequently, the principles of armed neutrality. were reflected in the 11th and 13th Hague Conventions of 1907 (rules of seizure of neutral commercial ships) and in the Nyon Agreement and the London Protocol of 1937 concerning the struggle against piratical submarine attacks on commercial ships.

In the contemporary period, military-technical progress and the extension of the concept of military contraband have weakened the significance of the principles of armed neutrality.