“Selma”, directed by Ava DuVernay and written by Paul Webb, is probably the most complete account of the (three) Selma-to-Montgomery civil rights marches in March 1965 in all visual media.
Update: Jan 3.
There is controversy, in the way some say that the film unfavorably portray's LBJ's hesitancy, CBS story here.
Update: Jan 13
Tim Lee on Vox Media explains Paramount's decision not to quote MLK's "I have a dream" speech directly, but to rewrite it, out of a very conservative use of copyright law and fair use, because of the possibly catastrophic result of a lawsuit from an estate known to be litigious, link here. There's an argument here to strengthen fair use or to shorten copyright terms.