The song describes graphically and metaphorically about the horrors of lynching, which was killing for and alledged offense without a legal trial. Lynching occured in many different ways, though hanging was the most common ones. There would often be dead bodies of black Americans hanging around in trees. That’s why the song compares the dead body to a strange fruit.
At the start of the twentieth century, such lynchings had reached a height of Southern United States with vast majority of victims being black. The writer of this song, Abel Meeropol originally wrote the song as a poem, he wrote this song upon seeing a postcard of a dead body hanging from a tree. The Americans do this as if they were proud of themselves. The poem eventually became a song and was sung by Billie Holiday, who made it famous.
I think the song and the writer himself is trying to pass us the message that we should believe that there is only one race, that is the human race. We shouldn’t judge people by their skin tone and we shouldn’t question their abilities just by looking at their skin tones. Moreover, I think that this song’s one of the most important messages is to stop racism and have respect for each other’s race. We all should treat others the way we want to be treated, not treat people looking at their skin tone.