The series launched as Harper Torchlights in September 1956, but the name had changed to Torchbooks by January 1957. Had exclusively religious focus early on.
1956 (September) - series launches as Torchlights with TL 1 - TL 6
1957 (January) - series renamed as Torchbooks starting with TL 7
1958 - first titles in the Cathedral Library, which will later be launched as a full sub-series (TB 301-)
1959 (September) - all prior Torchbooks titles (TB 1 - TB 54) are rebranded as the Cloister Library, and all titles from TB 55 forward will be part of the Cloister Library sub-series)
1959 (September) - first titles in the Science Library (TB 501-)
1959 (November) - first titles in the Academy Library (TB 1001-)
Cloister Library - TL 1 - TL 6 (1956), TB 1 - TB 149 (1956-1967)
-- Journal for Theology and the Church - TB 251 - TB 255 (1965-1968)
Cathedral Library - TB 35 & TB 44 (1958); TB 301 - (1964-)
Science Library - TB 501 - (1959-)
Academy Library - TB 1001 - (1959-1967)
Bollingen Library - TB 2001 - (1961-)
University Library - TB 3001 - (1962- ); TB 3501 - TB 3505 (1964)
Cathedral Library - TB 301 - (1964-)
Temple Library - TB 801 - (1965-1968)
Basic Books - TB 5001 - (1972-
??? - TB 2051 - (1985-1989) after the last titles were seemingly published in 1982, the series continued on through ISBNs , although the TB number was indicated on the spine as well
=== The separate sub-series seem to have ended with the spring 1967 titles. I think TB titles continued in the former Academy Library series, somewhere just after TB 1300. VERIFY. ===
As with other Harper & Row series from the mid-1960s, the letter appended as a suffix to the series number in 1965-1966 corresponds to the book's price:
F - $.95
G - $1.25 / $1.35
H - $1.45
J - $1.60
K - $1.75
L - $1.95
M - $2.25
N - $2.45
P - $2.75
Q - $2.95
T - $3.75
A number of titles originally published in the Cloister Library were given new series when reissued. These new series numbers reflected the titles' new homes in different sub-series. For example, TB 50 (1959), Elias Mircea's Cosmos and History, was reissued in the Bollingen Library as TB 2050, some time in the mid-1960s. Here are all the titles I've come across that were renumbered and issued in a new sub-series:
Elias Mircea's Cosmos and History, TB 50 (1959) --> TB 2050 (Bollingen Library)
F.C. Copleston, Medieval Philosophy, TB 76 (1961) --> TB 376 (Cathedral Library)
Pierre Teilhard de Chardin, The Phenomenon of Man, TB 83 (1961) --> TB 383 (Cathedral Library)
Gabriel Marce, Homo Viator: Introduction to a Metaphysic of Hope, TB 97 (1962) --> TB 397 (Cathedral Library)
These newly-renumbered titles are out of sequence with other titles in their respective sub-series.
Certain titles were (I assume) reprinted with HR numbers rather than TB numbers. Still trying to piece together the timeline, but here are some titles I've come across:
C.G. Coulton, Medieval Village, Manor, and Monastery, TB 1022 (1960) --> HR 1022 (?)
Dilthey, Pattern and Meaning in History --> HR 1075
Hugh Seton-Watson, Eastern Europe Between the Wars, 1918 - 1941 --> HR 1330 (1968?)
Charles Gibson (ed.), The Spanish Tradition in America --> HR 1351 (1968?)
Marc Ferro (ed.), Social Historians in Contemporary France --> HR 1571 (1972)
WorldCat - [kw:harper se:hr]
Harper "Torchlight" Religious Paperbacks Due in September, PW, May 21, 1956, at 2132.
Ad, 169 PW 2198 (May 28, 1956) (announcing a new quality paperback line called Harper Torchlights for publication in September 1956).
Religious Books and Related Titles—A Major Category of Paperbacks, PW, Feb. 17, 1958, at 73-78, 74-75 (detailing, in section labeled Publishers Review Progress, the first years of the Torchbooks line and noting that An Augustine Synthesis is the first title in the Cathedral Library, a Catholic sub-series of the Torchbooks).
Harper's New Paperback Science Library, PW, July 20, 1959, at 67-68 (announcing the new Science Library, which ran as a subseries of the Torchbooks, but also noting a reorganization of the series):
The current series of library-size paperbacks in the field of religion, which have been known simply as Torchbooks, will be regrouped by Harper as the Cloister Library, a division like the Science Library, of the overall Torchbooks paperback line.
Ad, PW, Aug. 31, 1959, at 10 (announcing 3 new Torchbooks sub-series: the Cloister Library, which will include all 60 prior Torchbooks titles; the Science Library in September; and the Academy Library in November).
Bollingen Library: New Harper Paperback Series, PW, May 15, 1961, at 23.
Harper Torchbooks Adds History Sub-Division, PW, May 7, 1962, at 40.
Harper Changing Cathedral Library Editorial Direction, PW, July 27, 1964, at 48.
Eugene Exman, THE HOUSE OF HARPER: ONE HUNDRED AND FIFTY YEARS OF PUBLISHING 298 (Harper & Row 1967):
In the field of supplementary or assigned reading in the universities, paperbacks have made and continue to make an important contribution. Material of this sort is supplied by Torchbooks and Colophon Books, the two quality paperback lines, with presently almost 700 titles available, the bulk of which are reprints of established scholarly works in various fields. Perennial Library, the latest paperback line, is lower-priced and aimed at school and college students with the emphasis on literature. Cass Canfield, Jr., is the publisher of these three paperback lines, which for the next fiscal year should produce net sales of nearly three million dollars.
Cass Canfield, UP AND DOWN AND AROUND: A PUBLISHER RECOLLECTS THE TIME OF HIS LIFE 231 (Harper's Magazine Press 1971).
It was during these years that Harper's became preoccupied with starting its own line of paperbacks to supplement our indirect interest in paperback publishing through stock ownership in Bantam Books. Melvin Arnold, then a religious-book editor under Eugene Exman, undertook to develop Torchbooks. an attractive-looking and carefully chosen series designed to appeal largely to college and graduate students. Torchbooks achieved immediate recognition and success and two other paperback lines were soon added: Perennial and Colophon, both of them aimed at a less scholarly and younger audience than Torchbooks. Although Perennial is now a fast-selling line, it ran into serious difficulties after a year or two due to overproduction, and when Arnold assumed general management responsibilities for Harper's, Cass, Jr. was chosen for the difficult task of getting our paperbooks back on the rails. He achieved this with firmness and skill so that Torchbooks, Perennial, and Colophon books, the three Harper paperback lines, are now very profitable.
Harper & Row to Consolidate Paperbacks, PW, June 14, 1985, at 58.
Jonathan D. Sarna, JPS: THE AMERICANIZATION OF JEWISH CULTURE, 1888-1988 227-28 (Jewish Publication Society 1989):
Arthur Cohen, president of Meridian Books, a house that specializes in quality paperbacks, undertook to answer these questions and reassure the Society that its fears were groundless. He was a trusted friend from the days when he was a student at the Jewish Theological Seminary, and though still only twenty-nine, he had already made a name for himself as an innovative pioneer in the publishing field. Now, in 1957, he proposed a cooperative agreement whereby Meridian would produce and help market selected volumes from the JPS backlist in return for some advance payment and a share in the royalties. Some of the trustees, conservative as ever, had misgivings about the scheme, but Edwin Wolf 2nd was exuberant. He praised Cohen's "interest and restless intelligence," gave a tongue-in-cheek reassurance that the covers of the proposed books would "not seduce buyers by a colorful display of Marilyn Monroe playing Bathsheba in her bath," and signed a one-year renewable contract covering six titles.
Twenty-four months later, after the books had been out for a year, the Society knew that Wolf's decision had been right. Its investment was more than repaid, it experienced a 25 percent increase in its general sale of books, largely due to the new paperbacks (which, it turned out, did not diminish hardback sales at all), and it had the satisfaction of seeing some 60,000 inexpensive copies of its books distributed, mostly by Meridian. Over the next six years many additional titles were reprinted, including several originally published by university presses that were now brought under the Society's imprint for the first time. Then, much to everyone's disappointment, the agreement with Meridian was ended, apparently because of problems that occurred after Cohen sold the firm to World Publishing Company and left the enterprise. Having itself in the interim learned much about the paperback field, JPS was soon able to come up with a new co-publishing agreement, this time with Harper and Row's Torchbook series. But that too proved short-lived. Thereafter, following the general trend in publishing, it undertook to independently publish and distribute its own paperbacks, which it continues to market to members and nonmembers alike.