Every year we honor the legacy of Martin Luther King Jr. in January. Here's everything you need to know about the holiday.

Originally released on home video, Dr. Martin Luther King Jr.: A Historical Perspective follows a more traditional approach to documentary filmmaking. Narrated by The Transformers voice actor Arthur Burghardt, we see some never-before-scene footage of Dr. King and elements of his life that weren’t covered in the previous documentaries.

Between 1957 and his assassination on April 4, 1968, at age 39, Martin Luther King Jr. gave 2,500 speeches, wrote sermons and homilies and published five books. Meanwhile, the number of books written about King surely number in the thousands.