Harvard College Library this week purchased the largest known private collection of papers, photographs and memorabilia relating to poet and former Harvard professor of modern languages Henry Wadsworth Longfellow.

The collection of 19th- and early 20th-century documents pertaining to Longfellow was sold for an undisclosed sum by literary publicist Victor Gulotta, who had amassed it over 14 years.

The new purchase augments Harvard’s already extensive Longfellow collection, which includes the prolific poet’s personal papers, and will be housed in Houghton Library, the University’s repository for rare manuscripts.

Leslie Morris, curator of manuscripts for the Harvard College Library, said the curatorial departments of the Harvard library system receive sales offers daily from book dealers.

However, the University libraries make “relatively expensive” purchases like the Longfellow collection only once per year, or once every five years, Morris said.

“Research potential” is the primary factor in determining the value of a collection, she said. Yet Harvard librarians have a “particular fondness” for Longfellow “because he bought books for the library during his trips abroad,” she said.

Gulotta said his goal in collecting was to find “the man behind the poetry.” What Gulotta found was a man distinguished by how he treated others.

“Longfellow seemed to be such a good-natured person. He always responded to letters from admirers and tried to help amateur writers,” he said.