This Martin Luther King postcard is by Ahimsa Graphics, © 1987 by Penny Jackim.
From the Wikipedia article on Martin Luther King Day:
The Birthday of Martin Luther King, Jr., often called Martin Luther King Day, is a United States holiday marking the birthdate of the Reverend Dr. Martin Luther King, Jr., observed on the third Monday of January each year, around the time of King's birthday, January 15. It is the only United States federal holiday commemorating an African American and one of only three to commemorate an individual person.
At the White House Rose Garden on November 2, 1983, Reagan signed a bill creating a federal holiday to honor King. It was observed for the first time on January 20, 1986.
On January 17, 2000, for the first time, Martin Luther King Day was officially observed in all 50 U.S. states. The day is marked by demonstrations for peace, social justice and racial and class equality, as well as a national day of volunteer community service.