CHICAGO (CBS) — President Barack Obama’s great uncle, Charles T. Payne, a World War II veteran and chemical engineer turned library pioneer, has died at the age of 89.

WBBM Newsradio’s John Cody reports Payne helped liberate the Ohrdurf subcamp of the Buchenwald Nazi concentration camp in Germany in April 1945.

After the war, he went to study chemical engineering at Kansas State University on a GI Bill, and then studied library science at the University of Chicago, where Obama would later serve as a constitutional law professor.

In the 1960s, Payne helped the University of Chicago library guide a major transition “from a paper-based environment to an electronic environment,” said U of C interim library director Alice Schreyer, who once worked with Payne.

She said Payne led the movement toward automated library systems, not only at the University of Chicago, but nationally.

He retired nearly 20 years ago. Before working for the university, he had worked as a chemical engineer for a number of industrial chemical companies, Schreyer said.

Payne’s wife of 50 years, Melanie Payne, said her husband died Aug. 1 in Chicago. He had been suffering non-Hodgkin’s lymphoma.