The first period of Latvian independence covers the time from the declaration of independence on 18 November 1918 to 17 June 1940, when the troops of the Soviet Union, crossing the Latvian border from the East and the South, invaded its territory and occupied the country.
The history of the Republic of Latvia as a democratic state started with the declaration of independence. On 15 May 1934, Karlis Ulmanis carried out a coup and established an authoritarian regime. On 6 August 1940, Latvia was incorporated into the USSR as the Latvian SSR, in June – July 1941 it was occupied anew and included in the composition of Ostland established by the Nazis, in the 1944 – 1945 it was occupied by the Red Army repeatedly. It was only on 4 May 1990 that Latvia became a democratic country once again; its independence was recognized internationally after 21 August 1991.