Czechoslovakia: Polity Style: 1918-1939

28 Oct 1918	the establishment of an independent Czechoslovak state is proclaimed in accordance with a law adopted by the Presidium of the National Council (Národní výbor) on 28 Oct 1918 (People's Newspaper, No. 297, 29 Oct 1918, p. 1; Czechoslovakia Law Collection—Czech edition, No. 2, 6 Nov 1918, p. 9) [1]
28 Oct 1918 - 29 Feb 1920	Československý stát ^cz \| Czechoslovak State [2]
29 Feb 1920	the Constitutional Charter of the Czechoslovak Republic is adopted by the National Assembly (Národní shromáždění) on 29 Feb 1920 (effective upon proclamation on the same day as defined by Art. VIII of the Law of 29 Feb 1920) (Czechoslovakia Law Collection, No. 26, 6 Mar 1920, pp. 255-267) [3]
29 Feb 1920 - 23 Nov 1938	Československá republika ^{cz sk} \| Czechoslovak Republic [4]
29 Feb 1920	the Czechoslovak language received the status of state and official language in accordance with a Constitutional Law adopted by the National Assembly (Národní shromáždění) on 29 Feb 1920 and promulgated the same day (Czechoslovakia Law Collection—Czech edition, No. 26, 6 Mar 1920, pp. 268-269) [5]
23 Nov 1938	the Slovak Province (Slovenská země ^cz \| Slovenská krajina ^sk) is recognized an autonomous part of Czechoslovakia in accordance with a Constitutional Law adopted by the National Assembly of Czechoslovakia (Poslanecká sněmovna ^cz \| Poslanecká snemovňa ^sk on 22 Nov 1938, Senát ^{cz sk} on 22 Nov 1938), effective on publication on 23 Nov 1938 (Czechoslovakia Law Collection—Czech edition, No. 99, 23 Nov 1938, pp. 1161-1164) [6]
23 Nov 1938 - 15 Mar 1939	Česko-Slovenská republika ^{cz sk} = (from 1 Jan 1939) Čes'ko-Slovac'ka Republyka (Чесько-Словацька Република) ^uk \| Czecho-Slovak Republic
1 Jan 1939	Czech, Slovak and the language of Transcarpathia are recognized as the languages used in legislation in accordance with an order of the government of the Czecho-Slovak Republic issued on 30 Dec 1938 (effective 1 Jan 1939) (Czechoslovakia Law Collection—Czech edition, No. 122, 31 Dec 1938, pp. 1334-1336)
14 Mar 1939	the Slovak Province is proclaimed the sovereign and independent Slovak State in accordance with a law passed by the Slovak Diet (Slovenský snem ^sk) on 14 Mar 1939 (Slovak Law Book, No. 1, 14 Mar 1939, p. 1) [7]
16 Mar 1939	parts of Czechoslovakia occupied by the armed forces of Germany are incorporated into the territory of the Greater German Reich (Großdeutsches Reich) and are placed under its protection as the Protectorate of Bohemia and Moravia in accordance with a decree of the Führer and Reich Chancellor of Germany issued on 16 Mar 1939 (Bohemia and Moravia Law Collection, No. 28, 17 Mar 1939, pp. 373-376) [8]

Full title (Czech): Zákon ze dne 28. října 1918 zřízení samostatného státu československého.
Also in official use (Czech): Československá republika.
Full title (Czech): Zákon ze dne 29. února 1920, kterým se uvozuje ústavní listina Československé republiky.
Československá republika was used in the title and articles of the Constitutional Charter.
Full title (Czech): Zákon ze dne 29. února 1920 podle § 129 ústavní listiny, jímž se stanoví zásady jazykového práva v republice Československé.
Full title (Slovak): Ústavný zákon zo dňa 22. novembra 1938 o autonómii Slovenskej krajiny.
Full title (Slovak): Zákon zo dňa 14. marca 1939 o samostatnom Slovenskom štáte.
Full title (German): Erlaß des Führers und Reichskanzlers über das Protektorat Böhmen und Mähren vom 16. März 1939; (Czech): Výnos Vůdce a říšského kancléře ze dne 16. března 1939 o Protektorátu Čechy a Morava.