How might the movie of To Kill a Mockingbird have been received by American society in the early 60's?
The film version of TKAM won two Oscars: one for best picture, and one for best actor, for Gregory Peck as Atticus. Remember; even in the 60's, despite legislation and Supreme Court decisions, Jim Crow was alive and well in the South, making the content of Harper Lee's novel quite controversial for its time. However, Lee believed her message was something that had to be said.
Those of us that lived through this period of time can answer the question for you, I believe. Remember that the Civil Rights legislation was not passed until 1964. TKAM was published in 1960 and the movie came out in 1962. Long into the next two decades, however, segregation may have been outlawed in the U.S., but prejudice was alive and well, especially in the South. So to answer how the movie was received by American society in the early 1960s, I think it depends on where you lived in the U.S. - the South or anywhere else.
I lived in the North, and I can tell you that civic minded Northerners welcomed the movie, as did most westerners, East-coasters, etc. However, it was not well-received in the South. When I was in high school at this time, we had a transfer student from Texas and to our horror, he told of witnessing blacks being dragged through the street tied to the backs of cars (I graduated in 1965). Many of us who were young people in the North at this time were clueless to what was going on with regard to segregation and prejudice in the South, and it was only when we saw these things on television that the horrors were finally exposed.
Harper Lee was a Southerner, as were many famous American writers like Flannery O'Connor, Truman Capote, Faulkner, etc., and although these writers were from the South, they were against racism. Harper Lee's novel and the movie that was made from it was effective because rather than present an anti-racism message in didactic form, it illustrated the horrors of racism by means of a poignant story. And, the story was written by a white person. Later, in the 1970s, famous black writers came on the scene with similar stories (Ernest J. Gaines' The Autobiography of Miss Jane Pittman, for example, and other works by Maya Angelou, Alice Walker, etc.), but TKAM was a groundbreaking novel and movie for the times.