Diedrich Hermann Westermann

Diedrich Hermann Westermann (24 June 1875 – 31 May 1956) was a German missionary, Africanist, and linguist.

He carried out extensive linguistic and anthropological research in the area ranging from Senegal eastwards to the Upper Nile.

His most important later publication Die westlichen Sudansprachen 1927a divided these into East and West Sudanic languages and laid the basis for what would become Niger–Congo.

In this book and a series of associated articles between 1925 and 1928, Westermann both identified a large number of roots that form the basis of our understanding of Niger–Congo and set out the evidence for the coherence of many of the families that constitute it.

Subsequently, he published the influential and oft-reprinted Practical Phonetics for Students of African Languages in collaboration with Ida C. Ward (1933).