[1] Martna was born in Kreis Wiek in the Governorate of Estonia (in present-day Pärnu County) and studied in a local village school.
As a young man, he was also active in Estonian national movement, publishing articles in Postimees and Sakala and collecting folklore material.
Mihkel Martna disseminated socialist ideas in Tallinn, at the end 1880s he lived in Tartu and tried to influence students there.
Together with Jaan Tõnisson and Karl Menning, Martna formed the board of the foreign delegation and he was the first representative of Estonia in Germany (1919).
Martna was one of the central figures in determining the political life of the Republic of Estonia, he was also a leading theoretician of the Estonian Socialist Workers' Party.