Jan Stankievič was born in the village Arlianiaty near Ashmyany. During World War I Stankievič served in the army of the Russian Empire. In 1917–1918 he began to actively participate in activities of Belarusian national organizations.
Jan Stankievič graduated from the Vilnia Belarusian Gymnasium in 1921, the Charles University in Prague in 1926, became Doctor of Slavonic philology and history. In 1928-1932 he worked as a Belarusian language professor in the University of Warsaw and in 1927–1940 - in the University of Vilnius.
In 1928–1930 Dr. Stankievič was member of the Polish Sejm. As a politician, Stankievic advocated closer ties of Belarus and Poland, for what he has been often criticized by other West Belarusian politicians. He also actively proposed the name of Great Lithuania for Belarus considering Litvin traditions of Belarusian statehood.
In 1940 Stankievič went to Warsaw and joined the pro-German Belarusian Committee. He also established contacts with Polish antifascist resistance and created a pro-Polish Belarusian undercover group called the Belarusian Nationalist Party.
In fall 1941 Stankievič has moved to the German-occupied Minsk, where he worked at the science department of the Belarusian Central Rada. He was member of the Belarusian Self-Help and was among founders of a Belarusian Scientific Society.
In 1944 Jan Stankievič emigrated to Germany with retreating German military.
In 1949 he moved to the United States where he continued his work. Jan Stankievič was an active member of the Belarusian diaspora.
- «Крыўя-Беларусь у мінуласьці»
- «Курс гісторыі Крывіі-Беларусі»
- «Этнаграфічныя й гістарычныя тэрыторыі й граніцы Беларусі»
- «Повесьці й апавяданьні беларускіх (крывіцкіх) летапісцаў»
- «Беларускія плямёны»