Leo Wiener argues that Germanic languages arose by a sudden influx of Low Latin and Arabic. He demonstrates that they developed from the Graeco-Latin glossaries through Gothic interpretations, which themselves owe their origin to the Graeco-Arabic learning of Spain.

The author was the Professor of Slavic Languages and Literature at Harvard University, and authored many books including A Commentary to the Germanic Laws and Mediaeval Documents, History of Yiddish Literature, and was a contributor to German, Russian, French, English and American philological periodicals.