Robert Ebert was born in Mount Vernon, New York, in 1944. He attended Union College, initially intending to study engineering and mathematics. He soon found himself drawn to the humanities, and especially to the study of language. He earned a B.A. from Union in 1966. After attending the Universität Erlangen-Nürnberg in 1966–67 as a Fulbright Fellow, Bob entered the graduate program in Germanic linguistics at the University of Wisconsin–Madison, where he was awarded an M.A. in 1968 and a Ph.D. in 1972. His first position in his field was as assistant professor of Germanic philology and linguistics at the University of Chicago, where he taught from 1972 until 1979 (with a year as a visiting assistant professor at the University of California–Berkeley). Bob came to Princeton as an associate professor of Germanic languages and literatures in 1979, and was promoted to professor in 1987.

In his five books and dozens of articles, Bob established himself as the leading scholar of Germanic linguistics in North America. His early work, including his first book, Infinitival Complement Constructions in Early New High German (1976) was in- formed by the principles of generative grammar. As his career developed, he drew increasingly on models in sociolinguistics. The major results of this new combination were two now-standard volumes on the historical syntax of the German language in the period 1300–1750. These books, together with several widely influential articles on syntax and word order, led to increasing recognition among the large community of linguists in Germany. The mark of this recognition was the invitation to co-author the first comprehensive grammar of the language in the late medieval and early modern periods. The Frühneuhochdeutsche Grammatik is a cornerstone of every reference library in the humanities.