BLOCKADE, in international law, is the right, in time of war, of rendering intercourse with an enemy's port unlawful on the part of neutrals; and it is carried into effect by an armed force (ships of war), which blocks up and bars export or import to or from the place blockaded. This right is described by all writers on the law of nations as clear and incontrovertible, having its origin in the soundest principles of maritime jurispro dene,e, sanctioned by the practice of the best times. It is explained on the reasonable theory, that if a potentate or government lays siege to a place, or simply blockades it, such potentate or government has a right to prevent any other power, or representative or subject of such power, from entering, and to treat as an enemy any one who attempts to enter the blockaded place, or iu any way assists the besieged, for such a person opposes the undertaking, and contributes to the miscarriage of it.
Lord Stowell laid it down that there are two sorts of B.—one by the simple fact only, the other by a notification accompanied with the fact. In the former case, when the fact ceases—otherwise than by accident or the shifting of the wind—there is frame diately an end of the 13.; but where the fact is accompanied by a public notification from the government of a belligerent country to neutral governments, the 13. must be sup to exist till it has been publicly repealed. This notification it is the duty of the belligerent country to make immediately. His lordship also explained that, on the queer Lion of B., three things must be proved: 1st, The existence of an actnal 13.; 2d, The knowledge of the party; and 3d, Some act of violation, either by going in or coming out with a cargo laden after the commencement of blockade. On this last point, the timo of shipment is very material; for although it might be hard to refuse a neutral liberty to retire with a cargo already laden. and by that act already become neutral property, yet, after the commencement of a B., a neutral cannot be allowed to interfere in any way to assist the exportation of the property of the enemy. After the commencement of a 13., a neutral is no longer at liberty to make any purchase in that port. But the most essential element is actual B., and this state of things can only be proved to the satisfac tion of a court of justice by the ships stationed on the spot to maintain the 13. using
their force for that purpose. A B., therefore, is only to be considered as exist ing when there is a power to enforce it.
To be valid, a B. must be accompanied by actual investment of the place, and it may be more or less rigorous, either for the purpose of watching the operations of the enemy, or. on a more extended scale, to cut off all access of neutral vessels to that interdicted place, which is strictly and properly a B.; for the former is in troth; no 13. at all as far as neutrals aro concerned. But to be binding on neutrals, it ought to be shown that they have knowledge or may be presumed to know of the B.; and this knowledge may arise in two ways—either by such a public and formal notification as we bare already described, or by the notoriety of the fact. Yet it is at all times most convenient that the B. should be declared in a public and distinct manner, instead of being left to creep ont from the consequences produced by it; and the effect of such notification to the neutral government is clearly to include all the individuals subject to the latter.
The breach of B. may be either by coming out of the blockaded port, or going in, such breach, however, may sometimes be excusable. It has been decided that intoxica tion on the part of the master of a ship will not be received as an excuse. That breach cif B. subjects the property employed for that purpose to confiscation is an established rule of the law of nations, and is universally acknowledged by all civilized govern ments. The violation of B. by the master, however, affects the ship, but not the cargo, unless the cargo is the property of the same owner, or unless the owner of the cargo is cognizant of the intended violation.
On the proclamation of peace, or from any political or belligerent cause, the con tinuance of the investment may cease to be necessary, and the B. is then said to be raised. The blockading force then retires, and the port is open as before to all other nations.—See the law on the subject of this article extremely well stated in A Manual of as Law of Maritime Warfare, by William 1Iazlitt and Henry Philip Roche, barristers-at law, 1854; see, also, ORDERS IN COUNCIL, BRITISIL