Historical Note on the Library of Congress Classification

In 1897 the decision was made to develop a new classification system for the Library of Congress. Charles Martel, chief classifier in the Catalogue Division between 1897 and 1911, oversaw the development of the new system, which was based on the million-volume collections of the Library. Mr. Martel drafted many of the early editions, aided by individual classifiers. In 1917 the Classification Division was formed, with Clarence W. Perley serving as chief classifier until 1937. He had previously been a classifier under Mr. Martel and had himself prepared early editions of a number of schedules. In 1941 the Classification Division and the Catalogue Division were reorganized into the Subject Cataloging Division and the Descriptive Cataloging Division. Responsibility for developing the schedules and classifying materials was assigned to the new Subject Cataloging Division, which also took on the other task of subject analysis, that of creating and assigning subject headings. In 1989 the responsibility for preparing and publishing the schedules and for providing policy guidance was transferred to the Office for Subject Cataloging Policy when that office was separated from the Subject Cataloging Division. Under a 1992 reorganization of cataloging at the Library of Congress, these responsibilities were absorbed into the newly created Cataloging Policy and Support Office.

The original organization of the classification was according to broad disciplines as seen a century ago. Since interdisciplinary topics were difficult to accommodate in this system, many arbitrary choices have been made over the years. Each schedule was developed separately, following its own internal logic. The order of topics, types of captions, level of detail, form of notes, etc., reflects the material being classified and the style of those involved in its creation, application, and development. As a result, each schedule has unique features, and it is difficult to generalize about the schedules as a whole.

The current published classification schedules are the result of the combined efforts of catalogers, editors, and policy specialists. Catalogers propose new or changed class numbers when required by new material being cataloged, and formulate major developments as time permits. Editorial staff cumulate the new proposals, determine the exact wording of anchor points, annotation instructions, and index entries, and produce a list for review by policy specialists and other staff at the weekly editorial meeting. The developments approved at the editorial meeting are published in the quarterly LC Classification: Additions and Changes.

An attempt is made to produce at least two new "cumulative" editions of LC schedules each year. Editorial staff input text for cumulative editions, editing existing text to conform to current practices and indexing the completed volume. Occasionally contracts are let to input text for these editions. Policy specialists provide overall guidance and many edit the subject contents of schedules. New law schedules are developed by the law classification specialist in the Cataloging Policy and Support Office.

Order of Publication of the Original Editions of the LC Schedules