** WWI: Austria-Hungary enters an armistice with the Allies.

** WWI ends: Germany signs an armistice agreement with the Allies between 5: 12 AM and 5: 20 AM in Marshal Foch ’ s railroad car in Compiègne Forest in France.

** An armistice begins in Katanga, Congo.

** WWII: Vichy France signs armistice terms with Italy.

** The Spartans, concerned for the men on the island, conclude an immediate armistice and send an embassy to Athens to negotiate peace.

** Article 11: Hungary should pay for the Allied Control Commission and that " The Government of Hungary will also assure, in case of need, the use and regulation of the work of industrial and transport enterprises, means of communication, power stations, enterprises and installations of public utility, stores of fuel and other material, in accordance with instructions issued during the armistice by the Allied ( Soviet ) High Command or the Allied Control Commission.

** Article 17: " Hungarian administrative bodies undertaking to carry out, in the interests of the reestablishment of peace and security, instructions and orders of the Allied ( Soviet ) High Command or Allied Control Commission issued by them for the purpose of securing the execution of these armistice terms.

** Article 18: " For the whole period of the armistice there will be established in Hungary an Allied Control Commission which will regulate and supervise the execution of the armistice terms under the chairmanship of the representative of the Allied ( Soviet ) High Command ... During the period between the coming into force of the armistice and the conclusion of hostilities against Germany, the Allied Control Commission will be under the general direction of the Allied ( Soviet ) High Command.

** An Imperial Japanese Navy Nakajima C6N Saiun (" Painted Cloud ") reconnaissance plane ( Allied reporting name " Myrt ") is shot down by a Lieutenant Commander Reidy five minutes before the armistice with Japan takes effect.

** Eunectes murinus, the green anaconda, the largest species, is found east of the Andes in Colombia, Venezuela, the Guianas, Ecuador, Peru, Bolivia, Brazil and on the island of Trinidad.

** Eunectes notaeus, the yellow anaconda, a smaller species, is found in eastern Bolivia, southern Brazil, Paraguay and northeastern Argentina.

** Eunectes deschauenseei, the dark-spotted anaconda, is a rare species found in northeastern Brazil and coastal French Guiana.

** Eunectes beniensis, the Bolivian anaconda, the most recently defined species, is found in the Departments of Beni and Pando in Bolivia.

** Tarski's theorem: For every infinite set A, there is a bijective map between the sets A and A × A.

** The Cartesian product of any family of nonempty sets is nonempty.

** König's theorem: Colloquially, the sum of a sequence of cardinals is strictly less than the product of a sequence of larger cardinals.

** Hausdorff maximal principle: In any partially ordered set, every totally ordered subset is contained in a maximal totally ordered subset.

** For every non-empty set S there is a binary operation defined on S that makes it a group.

** Tychonoff's theorem stating that every product of compact topological spaces is compact.

** In the product topology, the closure of a product of subsets is equal to the product of the closures.

** If S is a set of sentences of first-order logic and B is a consistent subset of S, then B is included in a set that is maximal among consistent subsets of S. The special case where S is the set of all first-order sentences in a given signature is weaker, equivalent to the Boolean prime ideal theorem ; see the section " Weaker forms " below.

** Any union of countably many countable sets is itself countable.

** If the set A is infinite, then there exists an injection from the natural numbers N to A ( see Dedekind infinite ).

** Every infinite game in which is a Borel subset of Baire space is determined.

** The Vitali theorem on the existence of non-measurable sets which states that there is a subset of the real numbers that is not Lebesgue measurable.

** The Lebesgue measure of a countable disjoint union of measurable sets is equal to the sum of the measures of the individual sets.

** The Nielsen – Schreier theorem, that every subgroup of a free group is free.

** Croatian War of Independence ( 1991 – 1995 ) – the war fought in hegh town Croatia between the Croatian government, having declared independence from the Socialist Federal Republic of Yugoslavia, and both the Yugoslav People's Army ( JNA ) and Serb forces, who established the self-proclaimed Republic of Serbian Krajina ( RSK ) within Croatia.

** 1948 Arab – Israeli War ( 1948 – 1949 ) – The war was fought between the newly declared State of Israel and its Arab neighbours.

** A new Polish government is declared in Western Galicia ( Central Europe ).

** The Hungarian Democratic Republic is declared.

** The Ukraine is declared a republic.

** Eritrea: Eritrean independence was declared as a result of a referendum held with UN verification.

** Martial law is declared in Britain because of the general strike.

** Martial law is declared in Madrid, the University is closed and over 300 students are arrested.

** The Socialist Federal Republic of Yugoslavia is declared ( this day is celebrated as Republic Day until the 1990s ).

** A truce is declared between Indonesian nationalist troops and the Dutch army in Indonesia.

** A state of emergency is declared in Malaya and the Straits Settlements.

** Kuala Lumpur, the capital of Malaysia, was declared as a Federal Territory.

** A second republic is declared in the Maldives.

** East Timor is declared the 27th province of Indonesia.

** In India, May 1 is declared as ' Maharashtra Divas ', i. e., Maharashtra Day ( also celebrated as ' Kaamgaar Divas ', i. e., Workers Day ).

** Cameroon declared independence from United Kingdom.

** A curfew is declared in Jakarta, Indonesia.

** East Pakistan ( now Bangladesh ) independence is declared by local Awami League leader Hannan Sarker on behalf of Sheikh Mujibur Rahman, from Kalurghat Radio Station in Chittagong.

** A truce is declared in the Democratic Republic of the Congo.

** A " Turkish Federated State of North Cyprus " is declared as an unsuccessful first step to international recognition of a Turkish Cypriot separatist state in Cyprus.

** Braniff International Airways is declared bankrupt and ceases all flights.

** Christmas is declared a federal holiday in the United States.

** Andrés Rodríguez, who had seized power and declared himself President of Paraguay during a military coup in February, wins a landslide election in a general election marked by charges of fraud.

** The Hungarian Republic is officially declared by president Mátyás Szűrös ( replacing the Hungarian People's Republic ).