The movie subtitles state the events began in 1702. In fact Asano's crime took place on April 21, 1701. The revenge on Kira took place on January 30, 1703, not on December 14, 1702. The samurai committed seppuku on March 30, 1703, not on February 4, 1704.
All these errors result from wrong conversion of Japanese dates to Gregorian calendar.
The movie version has all forty-seven Ronin committing seppuku at the end. Only forty-six did so. One was pardoned by the Shogun. He lived to age seventy-eight and died a natural death. He is buried with his forty-six comrades at the famous temple of Sengaku-ji.