After graduating in 1901, he received his bachelor of philosophy in 1910 and worked for the national archive from 1912 to 1917.

At the University of Helsinki, Dahlström was the secretary of the student society Prometheus, an organization promoting freedom of religion; he worked together with philosopher and sociologist Edvard Westermarck.

He was awarded a licentiate of philosophy in 1929; his thesis was on the Great Fire of Turku and the history of the city's buildings.

Dahlström founded the Turku-Area Song and Music Society (Åbolands sång- och musikförbund) in 1922, of which he was long chairman, and he was the initiator of the Finnish Swedish Song and Music Society [sv] (Finlands svenska sång- och musikförbund) in 1929.

Under the pseudonym Père Noble he published Sommar (stories, 1917) and Bokslut (poetry, 1939).