As the legal and academic worlds mourn the loss of one of the era's greatest minds, a flood of tributes point to yet another side of Harvard legal scholar Charles J. Ogletree Jr., who died on Friday: that of a selfless mentor.

Ogletree, who passed away at the age of 70 after a long fight with Alzheimer's, was a trailblazer in advocating for civil rights. Among his accomplishments were the founding of the Criminal Justice Institute—a program at Harvard Law School that trains students to represent indigent defendants—and his work to seek reparations for the survivors of the 1921 Tulsa Race Riot.

Behind the scenes, though, Ogletree was also paving the way for the next generation of lawyers and activists—even when he was busy with an extremely packed schedule.

“He always found the time to talk to students, and take them to lunch, give them career advice,” said Ronald Sullivan Jr., the director of the Criminal Justice Institute. “He always found time to do what he thought was important, and that's to pass things on to the next generation of lawyers.”

Ogletree was a source of guidance for future leaders like Barack and Michelle Obama, who both went to Harvard Law School when Ogletree was teaching.

In a statement, former President Obama said Ogletree’s reputation preceded him at Harvard.

“He took time on weekends to run something called 'Saturday School' for Black students who didn’t necessarily have the support systems at home to get them through the difficult first years of law school,” the statement read. “Eventually, Saturday School became so popular that students of every background began showing up to hear Charles explain things in a way they could understand. It was an example of the kind of person Charles has always been: unfailingly helpful, and driven by a genuine concern for others.”

"I was fortunate to learn from Professor Ogletree as a beginning law student and then again as the executive director of the National Bar Association," tweeted Demetris Cheatham, who was the first woman to lead that organization. "He poured into the cup of so many."

It's that sort of guidance that may be what is remembered most by those who knew him.

Ronald Sullivan first met Ogletree, better known by many as simply "Tree," when Sullivan entered Harvard Law School as a student. Sullivan went on to become a research assistant for Ogletree, a babysitter for his children and eventually the director of the Criminal Justice Institute.

While Ogletree’s work representing high profile clients like Tupac Shakur and Anita Hill might have helped make him a big name, Sullivan said the impact he made on the lives of everyday people was nothing short of amazing.

“Day in and day out, his phone never stopped ringing. And Tree rarely, if ever, said 'no,'” Sullivan said. “He was a man who was service-oriented. He gave and gave and gave and that seemed to be his mission in life.”

Charles J. Ogletree Jr. had a familiarity with the less fortunate: he grew up poor in Merced, California, raised by seasonal farm laborers before attending Stanford University, then Harvard.

In a message to the campus community, Harvard Law School Dean John F. Manning said Friday that Ogletree had a "monumental impact" on the school.

"His extraordinary contributions stretch from his work as a practicing attorney advancing civil rights, criminal defense, and equal justice to the change he brought to Harvard Law School as an impactful institution builder to his generous work as teacher and mentor who showed our students how law can be an instrument for change," he said.