1938 treaty on Hungary's boundaries
The First Vienna Award was a treaty signed on 2 November 1938 pursuant to the Vienna Arbitration, which took place at Vienna's Belvedere Palace. The arbitration and award were direct consequences of the previous month's Munich Agreement, which resulted in the partitioning of Czechoslovakia.
Though some from the government called for military action, Hungarian revisionism primarily aimed to restore the historical boundaries peacefully. In the interwar period, Hungary was weaker economically and militarily than the neighbours against which it had territorial claims. Nazi Germany and Fascist Italy had supported the territorial claims of the Kingdom of Hungary, and revision of the 1920 Treaty of Trianon. Nazi Germany had already violated the Versailles Treaty by the remilitarization of the Rhineland (7 March 1936) and the "Anschluss" of Austria (12 March 1938).
The First Vienna Award separated, from Czechoslovakia, territories in southern Slovakia and southern Carpathian Rus' which were mostly Hungarian-populated and returned them to Hungary. Hungary thus regained some of the territories (now parts of Slovakia and Ukraine) which Hungary had lost after World War I under the Treaty of Trianon. Czechoslovakia also ceded to Poland small patches of land in Spiš and Orava regions.
In mid-March 1939 Adolf Hitler gave Hungary permission to occupy the remainder of Carpathian Rus' (officially known as Carpatho-Ukraine since December 1938). This advanced Hungary's territory northward, up to the Polish border, thereby restoring a common Hungarian–Polish border, which had existed before the 1772 First Partition of Poland-Lithuania. Before the end of World War I and the Treaties of Trianon and Saint Germain, the Carpathian region of the former Kingdom of Hungary (Transleithania) in Austria-Hungary had, to the north, bordered the Kingdom of Galicia and Lodomeria, a constituent part of Austria's Cisleithania.
Six months after Hungary occupied the remainder of Carpathian Rus', in September 1939, after the German invasion of Poland, the Polish government and tens of thousands of Polish soldiers (including airmen and ground crews) including Stanisław Maczek's 10th Motorized Cavalry Brigade 
as well as volunteers (collectively known as "Sikorski's tourists" by reference to an official statement by Joseph Goebbels) evacuated to internment Hungary and Romania, from where (thanks partly to the tacit acceptance local governments) were able to go on to on to France and to French-mandated Syria to fight in the Polish Armed Forces in the West. 
After World War II, the 1947 Treaty of Paris declared the Vienna Award null and void.
Background.
International situation.
From 1933 Hungary closely coordinated its foreign policies with those of Nazi Germany, in the hope of revising Hungary's borders as established in the 1920 Treaty of Trianon. In March 1933 Hungary's prime minister declared that Hungary "wanted justice on the historical principle" and desired the restoration to Hungary of Hungarian-inhabited territories that Hungary had lost after World War I. In June 1933 Hungarian Prime Minister Gyula Gömbös visited Germany, meeting with Adolf Hitler, and they concluded that Czechoslovakia was a principal obstacle to a "rearrangement" of Central Europe and therefore should be subverted internally, isolated internationally, and finally eliminated by military force. During a meeting with Hitler in August 1936, Miklós Horthy advocated a common attack against Czechoslovakia to excise a "cancerous tumor from the heart of Europe".
In late 1937 Hitler decided to open a campaign against Czechoslovakia. In 1938 Germany and Hungary focused on creating a common platform to that end, and in November 1938 Hitler negotiated with the Hungarian government concerning the fate of Czechoslovakia.
Hungarian representatives considered an overt attack on Czechoslovakia too dangerous and wanted to preserve that country's relations with France and Britain, whose support in the question of Hungarian minorities was conditional on Hungary's not joining with Germany in military actions. This outraged Hitler and led to a change in Germany's view of Hungarian territorial demands in eastern Czechoslovakia.
Before the Munich Agreement, a Hungarian government emissary had officially asked the German and Italian delegations to resolve Hungarian demands together with the questions of Sudeten Germans. However, Hitler did not agree because he was not satisfied with the previous passivity of Hungary and because he had his own plans for Central Europe. The French and British delegates, Prime Minister Édouard Daladier and Neville Chamberlain, saw potential danger in such a complex solution, but the Italian delegate, Prime Minister Benito Mussolini, allowed Hungarian demands to be reflected in an appendix to the agreement. It requested Czechoslovakia to resolve questions with Hungary and Poland within three months by bilateral negotiations, or matters would be resolved by the four signatories of the agreement.
After the acceptance of the ultimatum concerning Trans-Olza, which had been annexed by Czechoslovakia in 1920 after the Czechoslovak invasion that triggered the Polish-Czechoslovak War, up to the armistice line, and smaller disputed border areas by Poland, the Hungarian question had remained open. Poland later annexed further small border territories in northern Slovakia (on 1 December 1938, villages in Kysuce, Orava and Spiš) comprising 226 km2, with 4,280 inhabitants (see separate article, Polish–Czechoslovak border conflicts). The Hungarian government understood the appendix of the Munich Agreement as an agreement of the Great Powers for the revision of peace treaties and emphasised that it did not mean only the revision of borders based on ethnicity but also the eventual restoration of Hungarian territory before 1918 and the creation of a common border with Poland. Official Hungarian circles were aware that Hungary alone was too weak to enforce its territorial demands towards Czechoslovakia because they knew that any attack would encounter the resistance of the more modern Czechoslovak Army.
Therefore, Hungary decided to fight Czechoslovakia in the diplomatic field instead and to push for territorial revision in the spirit of Munich Agreement.
Border conflicts and sabotage.
The Munich Agreement had defined a three-month period to resolve Hungarian demands, but the Hungarian government pushed to start negotiations immediately. The pressure was increased by the Hungarians with border conflicts and diversion actions in Czechoslovakia. The first conflict occurred in the early morning of October 5, 1938, when troops of the Royal Hungarian Army crossed the border and attacked Czechoslovak positions near Jesenské with the goal of capturing Rimavská Sobota. Hungarian troops withdrew after the arrival of Czechoslovak reinforcements, which killed nine Hungarians and captured prisoners. Two days later, Hungarian troops again attempted to cross the Danube near Parkan (Párkány). The Czechoslovak situation was worse in Carpathian Ruthenia, with its lower density of fortifications; there paramilitary units of the Rongyos Gárda infiltrated Czechoslovakia. The first two units of the Rongyos Gárda crossed the border on October 6, 1938, and two days later, they blew up the bridge over the Borozhava River.
Such actions continued during the negotiations and after the First Vienna Award. During the second day of bilateral negotiations (October 10, 1938), Hungarian troops murdered a railway officer in Borozhava and damaged railway facilities.
Internal situation in Czechoslovakia.
Czechoslovakia had an interest in stabilising the situation because its foreign ministry had to resolve problems with Poland and Germany and did not want to start negotiations before October 15. The Czechoslovak minister of foreign affairs was focused on building new relationships with Germany and Italy to negotiate guarantees for new borders. After the Munich Agreement, all political subjects in Slovakia concluded that it is necessary to change the Slovak position and declared its autonomy on October 6, 1938. The new autonomous government understood the definition of borders as a priority, and the Slovak People's Party requested to participate in the negotiations. The central government in Prague was aware that the delegation should be led by a Slovak and considered Milan Hodža or Imrich Karvaš. However, after the creation of an autonomous government, Foreign Minister František Chvalkovský proposed its representatives: Jozef Tiso or Ferdinand Ďurčanský. Both politicians at first refused on the justification that the role was in competition with the central government. After it had been emphasised that it is mainly the interest of Slovakia, they decided to accept. Moreover, Tiso hoped that his Hungarian partners would more likely accept concessions if they did not negotiate with representatives of the central government.
Under the pressure of the threat of internal destabilisation of Czechoslovakia because of diverting actions and the further radicalisation of the situation in Hungary, Czechoslovakia agreed to begin negotiations on October 9.
Pre-arbitration negotiations.
In Komárno.
Negotiations were held between October 9 and October 13, 1938, in Komárno, on the Slovak northern bank of the Danube River, just on the border with Hungary. The Czechoslovak delegation was led by Jozef Tiso, the prime minister of the autonomous government, without any experience with similar negotiations, and it included Ferdinand Ďurčanský, Minister of Justice in the Slovak cabinet, and General Rudolf Viest. The central government of Czechoslovakia was represented by Ivan Krno, Political Director of the Czechoslovak Ministry of Foreign Affairs, who held rank of Ambassador Extraordinary and Minister Plenipotentiary. Autonomous Carpathian Ruthenia was represented by Ivan Párkányi, who was a minister without portfolio. The Czechoslovak (Slovak and Ruthenian) delegation was not completely prepared for lack of time. By contrast, the Hungarian delegation comprised experienced individuals and was led by Foreign Minister Kálmán Kánya and Education Minister Pál Teleki. The Hungarian government welcomed the composition of Czechoslovak delegation and believed that it would be easier to influence the inexperienced Slovak politicians by promises. That expectation was not fulfilled since other Slovak delegates rejected any possibility of returning to Hungary.
The Hungarian government's strategy for the negotiations was to demand areas in which at least 50% of Hungarians lived according to the 1910 census. That formulation was chosen with respect to the signers of the Munich Agreement, but Hungary also requested areas that did not match those criteria. On the first day, Hungary supplied memorandum with the requested territorial changes. The Hungarians further demanded a plebiscite in the remaining territory in which Slovaks and Ruthenians would declare whether they wanted to be incorporated into Hungary.
Hungary demanded territories up to and including a line defined by Devín (Hungarian: "Dévény"), Bratislava ("Pozsony"), Nitra ("Nyitra"), Tlmače ("Garamtolmács"), Levice ("Léva"), Lučenec ("Losonc"), Rimavská Sobota ("Rimaszombat"), Jelšava ("Jolsva"), Rožňava ("Rozsnyó"), Košice ("Kassa"), Trebišov ("Tőketerebes"), Pavlovce nad Uhom ("Pálóc"), Uzhhorod (, Hungarian: "Ungvár"), Mukacheve ("Mukačevo", "Munkács"), and Vinogradiv ("Nagyszőlős"). The territory was 14,106 km2 (with 12,124 km2 in Slovakia and 1,982 km2 in Carpathian Ruthenia). It included 1,346,000 citizens (1,136,000 in Slovakia, 210,000 in Carpathian Ruthenia). According to the last census, 678,000 of them had declared a non-Hungarian nationality (553,000 in Slovakia, 125,000 in Carpathian Ruthenia) in 1930.
Hungary also requested the immediate takeover of two border towns from Czechoslovakia as a "goodwill gesture". The Czechoslovak delegation agreed on the railway town of Slovenské Nové Mesto (until 1918, it had been a suburb of the Hungarian town of Sátoraljaújhely) and the town of Šahy (). Both were occupied by Hungary on October 12.
The main difference between both parties' arguments was that the Hungarians presented the 1910 census figures, as had Germany during the Munich Conference, but Czechoslovakia presented the latest 1930 figures and contested the validity of the 1910 census. Later, Czechoslovakia also presented figures from Hungarian censuses before 1900. It considered the 1910 census as unacceptable because it represented the peak of Magyarization and differed from previous Hungarian and later Czechoslovak censuses as well as postwar censuses from other countries in which the Hungarian minority lived (Austria, Romania and Yugoslavia). Tiso noted that he, for example, had been counted as a Hungarian during that census.
Meanwhile, the Hungarian delegation did not accept the results of the Czechoslovak census and proposed to use the 1880 Hungarian census, before the peak of Magyarization, as a compromise. The Hungarians also did not agree on the definition of purely-Hungarian towns like Košice.
The request for a plebiscite on Slovaks and Ruthenians for rejoining Hungary was rejected by Czechoslovakia as irrelevant because the Munich Agreement did not address question of either nation, the idea violated the sovereignty of Czechoslovakia and the Ruthenian delegate declared that the Ruthenian nation (except communists) had already expressed its will to live in Czechoslovakia.
The Hungarian delegation rejected several Czechoslovak proposals, such as an offer to create an autonomous Hungarian territory within Slovakia. Kánya characterised the proposal as a "bad joke" and declared that it was "absolutely impossible to discuss this question". Czechoslovakia then offered to cede Great Rye Island (Slovak: "Žitný ostrov", Hungarian: "Csallóköz", 1838 km2, with 105,418 inhabitants, almost all of whom were Hungarians), the creation of a free port in the town of Komárno and a population exchange in the remaining frontier regions.
Hungary