He performed obligatory military service the following two years, beginning his studies in German and English philology, the history of art, pedagogy, and philosophy at the University of Göttingen in the summer of 1962, with the idea of becoming a high-school teacher.
Koerner returned to West Germany and spent the next four semesters at the University of Gießen, completing the exams for both the State Diploma and the M.A.
He developed the grand scheme of a thesis proposal on the history and evolution of Saussure's linguistic theory, persuading G. L. Bursill-Hall to act as supervisor.
Koerner started, in typical German fashion, with the compilation of a bibliography "on the background, development and actual relevance of Ferdinand de Saussure's general theory of language."
It was accepted for publication a year later, by which time he was busily writing up the dissertation, which was defended in 1971, with Dell Hymes as external examiner.
Winfred P. Lehmann of the University of Texas arranged for Koerner to come to Austin as a Social Scientist Research Associate immediately after his thesis defence.
He had his first meeting with John L. Benjamins, then exclusively an antiquarian and periodical trader, in Amsterdam in August 1972, and in subsequent exchanges they agreed to launch Historiographia Linguistica, the first journal devoted to the history of linguistics, and several associated book series, "Amsterdam Classics in Linguistics" and "Classics in Psycholinguistics", both making 19th and early 20th century texts available again with introductions by modern specialists, and notably "Studies in the History of the Language Sciences" (SiHoLS), in which so far 116 volumes have appeared.
In 1978 he organized in Ottawa the first International Conference on the History of the Language Sciences (ICHoLS), thus providing scholars in the field with a forum for the exchange of ideas and research results and projects.
[1] Koerner was a prime mover in establishing the Henry Sweet Society for the History of Linguistic Ideas (HSS) in Oxford in the Spring of 1984, and the North American Association for the History of the Language Sciences (NAAHoLS) during the annual meeting of the Linguistic Society of America held in San Francisco, California, in December 1987.
In 2002–2003 Koerner was, as an awardee of the Konrad Adenauer Research Prize of the Alexander von Humboldt Foundation, a visiting scholar, first at the University of Cologne and then at the Zentrum für Allgemeine Sprachwissenschaft in Berlin, with which he has been associated ever since.