If you're only acquainted with Williams from "Grey's Anatomy," here are five more things you might want to know:
2. He Knows His History
After graduating from Temple University with a double major in African American Studies and Film and Media Arts, Williams followed his parents' footsteps and taught high school English, American Studies and African Studies in the Philadelphia public school system for six years. "I've always been obsessed with history and taught history," he told Essence magazine in February 2015.
3. Making the Switch to Acting
Instead of telling stories from history, Williams decided he wanted to be part of the storytelling process. So in 2005, he started studying acting and the following year earned his first role in an episode of "Law & Order." In 2008, he made his film debut in "The Sisterhood of the Traveling Pants 2" and the year after that was cast in "Grey's Anatomy."
"I thought there are ways that we could tell stories that could have a lot of value in communities that are constantly being told that they've come from nothing," he told Essence last year. "I decided to participate in the storytelling process and learned that you can actually do a lot of good on camera, by really giving voice to characters and story lines."
4. He's Biracial
At the start of his speech, Williams thanked his parents, Johanna Chase, a professional potter, and Reginald Williams. His mother is Swedish, while his father is African American, with some Seminole, originally from Georgia. Both worked in the public school system and were in the audience Sunday night.
Being biracial has given the blue-eyed star access to both sides of the race spectrum. He told The Guardian last October, "I have access to rooms and information. I am white and I am also black. I am invisible man in a lot of these scenarios,” Williams said, referring to the Ralph Ellison classic. “I know how white people talk about black people. I know how black people talk about white folks. I know I am there and everyone speaks honestly around me."
5. He's Married
The couple are also parents to two children, Sadie, born in December 2013, and Maceo, born last August.