Swiss historical and comparative linguist known primarily for his monumental work on Sanskrit.

Influenced by his father, Wilhelm Wackernagel, a professor of Germanic studies at the University of Basel, he became interested in comparative linguistics and Sanskrit while studying at the University of Göttingen. In 1876 Wackernagel became Privatdozent (unsalaried lecturer) in classical languages at the University of Basel, and in 1881 he became professor of Greek language and literature. After having made a number of significant contributions to the historical and comparative study of Greek, he began work on his Altindische Grammatik (1896–1905, 1930; “Old Indic Grammar”), the comprehensive work for which he is chiefly known. He accepted a position at the University of Göttingen in 1902, remaining there until 1915, when he returned to the University of Basel. Many of his lectures were published in Vorlesungen über Syntax mit besonderer Berücksichtigung von Griechisch, Lateinisch, und Deutsch (1920, 1924; “Lectures on Syntax, with Special Consideration of Greek, Latin, and German”).