He participated in the pantomime ballet Det dubbla giftermålet by Jean-Rémy Marcadet opposite Margaretha Christina Hallongren, Hedda Hjortsberg, Joseph Saint-Fauraux Raimond and Carlo Caspare Simone Uttini the 1790–91 season.

He was admired for his beauty and grace and attracted the attention of King Gustav III of Sweden.

He married the Danish singer Johanna Elisabeth Morthorst who were active at the theatre in Copenhagen in 1784–1827.

Dahlén accepted a young Hans Christian Andersen as a ballet student in spite of his lack of talent.

There stoof I for whole mornings, with a long stoff, and stretched my legs; but notwithstanding my good-will, it was Dahlén's opinion that I should never get beyong a figurente.