Kārlis Ulmanis came from a family of prosperous Latvian peasants. He studied at the Aleksander Gymnasium in Jelgava, at the Jelgava Realschule. Ulmanis studied agriculture in Germany, Switzerland, and the USA. He headed agricultural societies in the Courland and Livonian governorates, collaborated with Selskokhozyaystbennik [Agriculturist] magazine. December 1905 saw him imprisoned in Pskov for the content of his articles, which was disloyal to the authorities. He was released in May 1906. Until 1913 he had lived abroad.

In 1914–1916, he was editor of Zeme (Land) journal of the Baltic Society of Agriculture. In 1916, Ulmanis was elected to the board of the Baltic Committee for the Provision of Latvian Refugees. In March 1917, he was elected to the Vidzeme Provisional Zemstvo [local] Council. In April, he was appointed Deputy Commissar of the Provisional Government in the Governorate of Livonia. An organizer of the Latvian Peasant Union party, he held the post of Chairman of the Central Board (end of April 1917). During the occupation of Latvia by Germany, he lived in Riga (1917–1918).

In November 1918, Ulmanis was among the initiators of the establishment of the People’s Council of Latvia and the proclamation of Latvian independence. Since November 1918, he was Chairman of the Provisional Government of Latvia. On April 16, 1919, the German military, who accounted for the majority in the army of the Republic of Latvia, overthrew the Ulmanis’ government, substituting it for a pro-German cabinet.

Latvian ministers took refuge under the protection of the Entente fleet on board the Saratov ship in the roadstead in the Baltic Sea. To preserve the national statehood of Latvia, Ulmanis addressed the governments of Denmark, Sweden, and Estonia requesting support. On June 23, the Estonian-Latvian army defeated the German Latvian units in the battle at Cēsis. After negotiations mediated by the Entente, the government of Ulmanis headed Latvia again and returned to Riga. Until June 1921, he had been Prime Minister, Minister of Agriculture (July–September 1919), Minister of War (October 1919 – June 1920). During this period, he survived three assassination attempts.

In 1921–1925, Ulmanis was engaged in public activities. Later he again held a number of ministerial posts in the government of the Republic of Latvia, including the Prime Minister (1925–1926, 1931, 1934–1940). In May 1934, Ulmanis committed a coup d'état: he introduced martial law, dissolved the Sejm, and abolished the constitution. From 1936 to 1940, he combined the posts of President and Prime-minister. In July 1940, he gave up his resistance to the annexation of Latvia to the USSR and resigned. On July 22, 1940, he was deported to the Stavropol Territory. In June 1941, he was arrested and exiled to Turkmenistan. He died on September 20, 1942, in the Krasnovodsk prison hospital.