Harvard's president is dedicating a plaque in Harvard Yard to the slaves who played a role in the university's history.

The college says that until recently, those slaves and their contributions have been "all but invisible" on the campus.

University President Drew Faust is to be joined by members of Congress at a dedication ceremony Wednesday morning.

Faust announced last week in an op-ed in the student newspaper that the nearly 400-year-old institution would install the plaque at a former home for college presidents to recognize the slaves who lived and worked there. Slavery was abolished in Massachusetts in 1783.

Harvard also plans to host a conference on universities and slavery next year.