After a four-and-a-half-year vacancy, the Fletcher University professorship will be filled by Henry Louis “Skip” Gates Jr., Interim President Derek Bok announced yesterday.

Gates joins a prestigious group of 20 other faculty who are University professors.

“It’s without a doubt the greatest honor I’ve ever received, and I’m deeply humbled by President Bok’s generosity,” said Gates, who directs the W.E.B. Du Bois Institute for African and African-American Research.

“This is a great day for Harvard,” Alphonse Fletcher Jr. ’87, who endowed the position, wrote in an e-mail.

“I can’t think of a finer recipient of a University Professorship than Henry Louis Gates,” Fletcher said. “Working productively with three Harvard presidents, his collaboration with so many scholars, in so many fields, touching so many students and influencing the world well beyond the academy exemplifies what’s best in the leadership and scholarship of a modern university.”

At Fletcher’s request, Harvard removed the suffix “Jr.” a few years ago in order to honor Fletcher’s father, who along with his mother, sent their three sons to the University.

Gates serves as chairman of the selection committee of the Alphonse Fletcher Sr. Fellowship Program, which is administratively supported by the Du Bois Institute.

Cornel R. West ’74, who left Harvard for Princeton University after a much publicized squabble with former University President Lawrence H. Summers, was the previous occupant of the Fletcher chair.

“It makes it even more special that my dear friend Cornel West was the first incumbent of this professorship,” said Gates, who has been honored with a National Humanities Medal and a MacArthur Fellowship.

Last week, Af-Am Chair Evelynn Brooks Higginbotham informed the departmental faculty that West will not be returning to Harvard, a long-discussed rumor.

“He’s decided to stay because of the big initiative in Af-Am studies there,” said Gates, referring to Princeton’s recent decision to establish a Center for African American Studies.

Until his newest appointment, Gates was the Du Bois professor of the humanities. The former chair of the Af-Am department is widely considered to be one of the top scholars in his field.

“[Gates] has taken a field of study that, years ago, was floundering at Harvard and transformed it into the leading department of its kind in this country,” Bok said in a press release yesterday. “He has been one of the world’s intellectual leaders, if not the intellectual leader, in shaping the entire field of African-American studies over the last quarter century,”

Hired from Duke University in 1991, Gates has often called Harvard home to the “greatest center for African and African American studies”—a reference that he made possible with the recruitment of a slew of “Dream Team” professors. Even with the departures of members of that coterie, including West, Lawrence Bobo, and Gwendolyn Du Bois Shaw, Gates helped the department weather the exoduses and continued adding to the faculty ranks. Af-Am’s new chair, Higginbotham, leads a department boosted by the arrival of several new professors and an added focus on African Studies.

Even in the wake of seven major surgeries since 2000, Gates is hard at work. Last year he appeared onscreen in crutches for “African American Lives,” a four-hour PBS documentary in which he and other famous African Americans uncovered their ancestral roots,

“By mid-November, I should get my leg back,” said Gates, who trudges around the Square with crutches and a metal frame on his leg, for which he wears specially tailored wide leg pants.

These days, he also travels with a camera crew which is filming a PBS sequel to “African American Lives.” In “Oprah’s Roots,” Gates will teach audiences how to trace their own family trees as he traces Oprah Winfrey’s family background. The companion book, “Finding Oprah’s Roots: Building an African-American Family Tree,” will be available in February.

“I feel that what makes Gates so special is his ability to collaborate with the best and the brightest from Wole Soyinka, to Lawrence Summers, to Oprah, to Cornel West, from literature, to management, to history, to genetics,” Fletcher wrote.

—Staff writer Lulu Zhou can be reached at luluzhou@fas.harvard.edu.