Mr. Happy, with the exception of the Emancipation Proclamation, which was signed by President Lincoln, all the other events took place in the period between 1945 and 1975, and all were accomplished by sitting presidents. President Truman, a retired National Guard Colonel from Missouri, signed the bill integrating the militaary, President Eisenhower, a retired General of the Armies from Texas, sent the Federal Marshals and the National Guard into southern states to forcefully integrate the schools there, in accordance with the laws of the land at that time, and it was Johnson, a former Navy Commander also from Texas, who who pushed through his dream of "The Great Society" so blacks could get a fairer chance for work, schooling, and even welfare as needed.

Those times were mostly recent, and all of these people were US presidents who didn't need a black person, or person of color, to authorize those changes.

Dave