With the real Arthur the dog living until December 2020, six full years passed since the race that brought them together. Mikael Lindnord (the real life racer) has not adopted another dog since Arthur's passing. Furthermore, Arthur's death occurred just weeks before Arthur the King began filming.
Mark Wahlberg tore his knee on the first day of shooting and implemented the pain of his injury into his performance.
Even though shot & set in Dominican Republic, the actual real life events occurred in Ecuador.
It is based on the 2016 non-fiction book Arthur - The Dog Who Crossed the Jungle to Find a Home.
Arthur lived with Mikael Lindnord's family (on which the movie was based on) n Sweden for roughly six years. Unfortunately, Arthur the dog died in December 2020 after being diagnosed with a malignant tumor.