The "I Can See Clearly Now" singer's son confirmed his dad had died on Tuesday (06Oct20), revealing his father passed away at his home in Houston, Texas - prompting an outpouring of grief from stars who loved his music.
Nash's passing was particularly poignant for Cusack, as "I Can See Clearly Now" was prominently used in the soundtrack to his much-loved 1997 comedy thriller "Grosse Point Blank".
"Thank you mr Nash - for all the love in your music - and for letting us use your great song - RIP," he tweeted alongside a video of Nash performing his most famous song, before retweeting a number of fans posts mourning the star's passing.
"Culture Club" singer Boy George also paid tribute to the star as someone who had influenced his music immensely.
"R.I.P to the reggae legend Johnny Nash," he tweeted. "One of the artists who made me fall in love with lovers rock and reggae music in the early 70s. So many amazing tunes and a voice like silk. I have never really known a time with reggae music. He was one of the greatest."
SiriusXM host Eric Alper also marked the singer's passing, as did TV presenter and actress Holly Robinson Peete and fellow musician Rex Chapman.
The reggae world is also mourning the loss of another iconic musician Bunny "Striker" Lee. He recently passed away at the age of 79. He is survived by one son, Errol, who he shares with singer Marlene Webber.