Although the Classics Department in its present form did not exist at Johns Hopkins until recently, courses in Greek and Latin were offered from the time of the University's founding. In colleges and universities throughout the western world, a thorough grounding in the classics was considered an essential step in the preparation for any career. Thus, it is not surprising that the first full professor appointed by the Board of Trustees was the Professor of Greek, Basil Lanneau Gildersleeve. After receiving his Ph.D. in 1853 from the University of Gottingen, Gildersleeve had taught Latin and Greek at the University of Virginia before coming to Hopkins. President Gilman stated that Gildersleeve "concentrated his force upon Greek," while his colleague, Charles D'Urban Morris, taught Latin. A former professor at New York University, Morris had received his master's degree in 1852 from Oxford. In addition to overseeing the Latin section of the Classics Department, Morris advised undergraduate majors in the department, since Gildersleeve preferred supervising graduate students. Assisting in instruction was John Miller Cross, an 1870 Princeton graduate who was named Associate in Greek and Latin in 1876. The first courses offered covered Greek lyric poetry and both Greek and Latin elementary composition, and the first graduate seminars dealt with the works of Lucian and Aristophanes.

The Greek Seminary was founded in 1878 to give graduate students a forum in which to explore topics of interest to them. The emphasis that Gildersleeve placed on philology and textual criticism became further evident in 1880 when the American Journal of Philology was first printed. By 1883, the course selection in the department had expanded so greatly that an undergraduate major at Hopkins would have read, by the time of his graduation, every major classical author except Caesar. Also at this time, courses in New Testament Greek were begun as a complement to the works of the Classical period. A Latin Seminary was initiated in 1881 under the guidance of Minton Warren, a graduate of the University of Strassbourg who had been named to the faculty in 1879. The creation of a separate Latin Seminary further increased specialization within the department, allowing faculty members to devote more time to study in their own areas, thus leading to a higher quality of scholarship, both in classroom teaching and in research. In 1887, Herbert Weir Smyth, later a translator of Greek for the Loeb Classical Library, joined the faculty as an instructor in lyric poetry.

The American Journal of Philology was founded by Basil L. Gildersleeve in 1880 and has since been published in four quarterly issues. The Johns Hopkins University began publishing it in 1898. Although in the early years research concentrated on modern and ancient languages, because Gildersleeve was interested in classical literature, the Journal gradually devoted itself to classical studies.

The first decade of the twentieth century saw important changes in the leadership of the Latin and Greek Departments. The retirement of Minton Warren (a full professor since 1892) in 1900 and his subsequent replacement by Kirby Flower Smith as head of the Latin Seminary marked the beginning of a period in which Latin scholarship increased at Hopkins, and the traditional preeminence of the Greek Department was challenged.

In 1915, Gildersleeve retired after almost forty years as head of the Greek Department, and Charles William Emil Miller was appointed Chairman. Miller, a former student of Gildersleeve who received his Ph.D. in 1886, was a specialist in the meter and syntax of Greek poetry. A man of considerable intellectual talent, Miller had given up a career as a classical pianist to teach at Hopkins. Under his leadership, the amount of work published by faculty in the Department of Greek increased, including many articles in the American Journal of Philology. (See the Circulars, beginning 1914.)

The death of Kirby Smith in 1918 brought about another change of leadership. Tenney Frank, a graduate of the University of Chicago and an expert in Roman history, was named to head the Latin Seminary. Frank's appointment marked the first time that a head of one of the Classics Departments was not a linguist. The emphasis which Frank and his successors placed on historical and archaeological studies in addition to philological concerns was to have a powerful effect on the Classics Department as it exists today.

When Miller retired in 1933, he was succeeded as head of the Greek Department by Benjamin Meritt, a Princeton graduate whose main field of study was epigraphy. Meritt's term as Chairman was the shortest of any man who ever occupied the post; in 1935, after only two years, (the greater part of which was spent lecturing at the Institute of Advanced Study and Oxford) he resigned and accepted a professorship at Princeton. His replacement was David Robinson, holder of a Ph.D. from Yale and specialist in Hellenistic archaeology. Robinson made a name for himself by attempting to improve the rather stodgy image which the American public had of Classics professors at that time. An unconventional figure, he had entered the University of Chicago as an undergraduate at the age of fourteen and was the youngest man ever to be granted a degree by that institution. One of the first of Robinson's widely publicized deeds was the complete reconstruction in 1935 of a two thousand year old bathtub which he had discovered in pieces at an archaeological dig at Olynthus in Greece. Robinson also gained fame for his skill at identifying forged pieces of ancient art, a talent given wide coverage in local newspapers. Most unusual of all Robinson's deeds, however, was a talk which he gave at the Maryland Institute of Art in 1940 in which he compared the "classical beauty" of ancient Egypt's Queen Nefertiti and the Mona Lisa with a newly-painted portrait of Wallace Simpson, then Duchess of Windsor.

When the Second World War began, studies continued as usual in the department until the German invasion of Greece. Outraged over the ferocity of the fighting there, Robinson severed all ties between the Greek Department and German universities. Harold Cherniss, a professor engaged in editing a text by Aristotle on a grant from the Guggenheim Foundation, postponed that project and joined the army as a private. As in all departments of the University, enrollment in Greek and Latin courses dropped as students and faculty were called to national service. After the war, Robinson directed the Greek War Relief Fund, the proceeds of which aided Greece's post-war economic rebuilding. In 1946, coinciding with Robinson's retirement as Chairman of the Greek Department, the Departments of Greek and Latin were merged, along with courses in ancient history, archaeology and Sanskrit, to form the present Department of Classics.

The Chairman of this newly-formed department was Henry Rowell, who, like David Robinson, was a graduate of Yale and an archaeologist. Rowell had been appointed head of the Latin Department in 1939 after Tenney Frank died during a lecture series which he was giving at Oxford. An advocate of international cooperation in scholarship, Rowell encouraged greater use of the facilities of the American Academy in Rome and the American School of Classical Studies in Athens. During his term as Chairman, faculty participation in programs offered by those two schools increased, and by the time of his retirement, Hopkins professors were on the managing boards of both institutions. Rowell also stimulated interest in the activities of the American Philological Association. In the 1950s, as the scientific departments of the University gained prominence, interest among undergraduates in the Classics waned, and the department lost students and, consequently, faculty members. By 1960, the department had shrunk to the point that it contained only four members: Rowell; James Poultney, Professor of Sanskrit and comparative linguistics; John Young, Professor of archaeology; and James Oliver, professor of Greek literature and history.

In 1973, Henry Rowell retired after a term as head of the Classics Department second only in length to that of Basil Gildersleeve. He was replaced by Georg Luck, a native of Switzerland who received his Ph.D. from the University of Bern. The author of a landmark text on Latin love poetry, Luck had joined the faculty in 1971 as a visiting professor from the University of Bonn in West Germany. In 1976, he was replaced by Diskin Clay, a graduate of the University of Washington whose primary area of expertise is the works of the Greek historians. Clay held the chairmanship for seven years, until the appointment of Lowell Edmunds, in 1983. A specialist in Greek drama, Edmunds came to Hopkins after teaching at the Catholic University of America, Harvard University and holding the chairmanship of the Classics Department at Boston College. When Lowell Edmunds left, Jerrold Cooper from the Near Eastern Studies Department became the acting Chairman.

From 1982 until 1987, Diskin Clay served as editor of the American Journal of Philology, maintaining the tradition of naming a Hopkins professor to the editorship. At the completion of Clay's five-year term, Georg Luck served as temporary editor until 1988. Around this time, the senior faculty of the Classics Department departed for other institutions and the AJP relocated from Hopkins to the University of North Carolina, thus removing the most prestigious journal in the field from its founding home.

In 1993 Giulia Sissa was appointed chairperson. With the change in leadership came a new direction for the department: more focus on the "dialogue" between ancient, and contemporary thought.

Marcel Detienne became the newly created Basil L. Gildersleeve Professor. The endowed chair was bequeathed by the estates of Gildersleeves's daughter, Emma Gildersleeve Land and his granddaughter Katherine Land Weems in 1989.