President Obama and the first lady sent out Kwanzaa greetings Sunday, the first day of the seven-day celebration.

"Michelle and I extend our warmest thoughts and wishes to all those who are celebrating Kwanzaa this holiday season," Obama said in a statement. "Today is the first of a joyful seven-day celebration of African-American culture and heritage. The seven principles of Kwanzaa — Unity, Self-Determination, Collective Work and Responsibility, Cooperative Economics, Purpose, Creativity and Faith — are some of the very values that make us Americans."

The Kwanzaa holiday began in the U.S. in 1966. The week culminates with a feast and gift-giving.

"As families across America and around the world light the Kinara today in the spirit of umoja, or unity, our family sends our well wishes and blessings for a happy and healthy new year," Obama said.