Definition of "ultimatum"

. . But he was directed to present a memorial, urging many reasons for the restitution of the captures made before the war, to represent in its full force, the benefit that would arise, both to France and England, from the total desertion of the war in Germany, and if England should refuse the conditions, now offered as an ultimatum, to wait for farther instructions. The ultimatum arrived in London August 8. M. Buffy soon after wrote to Mr. Pitt, and in his answer, dated August 15, says, that, as to the stile of the ultimatum and letter, the king his master adheres both to the form and substance of them, he laments that peace appears by the proposals and conduct of France to be far distant, and retorts some charges and elusion and delay. M. Buffy, and Mr. Pitt however, had a conference on the two ultimatums jointly, and on the 30th of August an answer to the French ultimatum was delivered, in which the French propositions are agreed to, except in the following particulars. .

1762 The Annual Register or a View of the History, Politicks, and Literature of the Year 1761

An ultimatum may be issued containing a demand for satisfaction. Such an ultimatum is usually formulated in diplomatic terms, which would not make it too difficult for the state to which it is dispatched to find a way to adjust the difficulties. The ultimatum usually fixes the time within which an answer must be made. The United States required that Spain reply to its demand for withdrawal of Spanish forces from Cuba within three days; i. e., by April 23. War was declared on April 25. An ultimatum in itself does not necessarily involve a declaration of war unless the failure to comply with the demands carries with it a conditional declaration of war.The British demands upon Venezuela in 1902 required an immediate satisfaction of certain claims, and concluded: “ This communication must be regarded in the light of ultimatum.” The failure of Venezuela to satisfy these claims did not lead to an immediate war, but to an attempt to establish a pacific blockade which subsequently took the form of a true blockade. Whatever the preliminary negotiations or evidences of strained relations which might have received consideration prior to 1907, among those states now parties to the convention relative to the opening of hostilities, it is now necessary that there be a previous and explicit warning. This previous and explicit warning may take the form of a reasoned declaration of war or of an ultimatum with a conditional declaration of war. The reasoned declaration of war was regarded by many as necessary or at least very desirable because the opposing belligerent should be given a formal statement of the grounds of the war and the neutrals should not suffer such great changes in their ordinary rights and obligations without knowledge of the reasons. If instead of the reasoned declaration of war, the ultimatum with conditional declaration was employed, the reasons for the breaking off of peaceful relations would be stated in the ultimatum.

1913 U.S. Naval War College: International Law Topics and Discussions

. . Thirdly, That they, the Dutch, 5 or 6 Weeks after they had received these Letters, (of 12th of July) call'd for an Ultimatum, so they termed the dernier mot, from us; and that we gave our Ultimatum to the Mediators first by Word of Mouth in August, then on the 5th of September, N. S. in writing.

1724 William Wynne: The Life of Sir Leoline Jenkins, Judge of the High-Court of Admiralty