History’s greatest figures all had their defining characteristics.

Recall Martin Luther King Jr.’s charisma, former Prime Minister Margaret Thatcher’s iron will or World War II industrialist Oskar Schindler’s defiance in the face of one of the most powerful threats of the 20th century.

In the coming days and years, many will attempt to analyze and quantify what made Nelson Mandela such a legendary figure and effective leader. I think the answer is simple: his humanity.

Nelson Mandela died as he lived: quietly and without much pomp or circumstance. He didn’t have to live this way. Mandela had the world fighting for him and his ideals throughout his years in prison and after his release.

He had the world at his disposal. Everyone from heads of state to celebrities wanted to meet him — something we could only imagine doing.

It would have been all too easy for global adulation to seduce others with opportunities for personal or political gain.

Mandela could have crushed his former opponents and treated them to decade-long stints in prison, like they had done to him. But Mandela retained his humanity.

Like George Washington, he observed the limits of his power and knew when to give it up.

He forgave his opponents and went so far as to fully include them in a new South African government.

He worked not just for South Africa but for the world. This is evident in the way his words and ideals transcended traditional boundaries of race, ethnicity, nationality and class.

Mandela’s ability to see the good in people and society — even when they refused to see it in him — ultimately won many over to his side.  It’s a rare quality that only a few, like Mahatma Gandhi and Jesus Christ, have come to epitomize.

Already there’s talk of “the next Mandela,” but it’s futile. Leaders like Mandela only come once in a lifetime.

Now we can study Mandela’s legacy and work toward creating for ourselves the kind of rainbow nation Mandela had envisioned.