James H. Billington, a leading Russia scholar in 1987 when President Ronald Reagan nominated him to be the 13th librarian of Congress, will step down from his post on Jan. 1 after nearly three decades leading the world’s largest library, officials announced Wednesday.

The move comes after Dr. Billington, who turned 86 on June 1, presided over a series of management and technology failures at the library that were documented in more than a dozen reports by government watchdog agencies.

In a statement, Dr. Billington said he had informed President Obama and members of Congress of his intention to leave one of the central repositories of American cultural history.