Jan Krišjānovičs Pliekšan was born into the family of the tenant Krišjānis Pliekšans. He first studied at a German school in Daugavpils, which is now named after Rainis, and then graduated from the Riga City Gymnasium in 1884. From 1884 to 1888, he studied law at St. Petersburg University, where his materialistic worldview was formed. He began publishing in 1887, and from 1891 to 1895, he was the editor of the newspaper "Dienas Lapa." His first poems were published in 1895.

In June 1897, he was arrested, and in the Riga Provincial Prison, he completed the translation of Goethe's "Faust" into Latvian. In December 1897, Rainis was exiled to Pskov, and then in 1899 to the town of Slobodskoy in the Vyatka province, where he created a collection of poems "Distant Echoes on a Blue Evening," filled with revolutionary ideas.

In 1903, upon returning from exile, Rainis actively engaged in the struggle of the Latvian Social Democracy. He wrote the symbolic drama "Fire and Night," dedicated to the struggle and the eternal development of life. In 1905, the collection "Sowing the Storm" was published, and at the end of that year, he moved to Switzerland. There, he created the poetry collections "Quiet Book," "Those Who Do Not Forget," the plays "Golden Horse," "Indulis and Arija," as well as "I Played, I Danced," published in 1919. In the poem "Ave, sol!" he celebrates the sun as a symbol of freedom. The philosophical collection "End and Beginning" is dedicated to the proletariat. The play "Blow, Breeze!" holds an important place in Latvian dramaturgy, while in the tragedy "Joseph and His Brothers," Rainis explored themes of love and hatred, forgiveness and revenge.

In 1920, Rainis returned to Latvia. He created the tragedy "Ilya Muromets" based on Russian epics and published the poetry collection "Five Sketch Notebooks of Dagda."

He actively participated in the political life of the country. In 1917, the Mensheviks tried to include him in their list for the elections to the All-Russian Constituent Assembly, but they did not manage to obtain his consent in time. In 1920, Rainis was elected to the Constitutional Assembly of the Latvian Republic from the LSDRP and ran for the position of chairman, losing to Jānis Čakste. He was one of the authors of the Constitution of Latvia.

From 1921 to 1925, Rainis was the director of the National Theatre, and from 1926 to 1928, he served as the Minister of Education. On February 28, 1925, he became the first Latvian cultural figure to be awarded the Order of the Three Stars, 1st class.