Lee Marvin and Oliver Reed had a drinking contest, which Reed won after ten hours when Marvin fell unconscious.
Reportedly, lead cast members Lee Marvin and Oliver Reed were allegedly both involved in regular heavy drinking during production. For example, this was reported and discussed in a column by James Bacon in the 13th October 1975 issue of the 'Los Angeles Herald Examiner' newspaper.
The period of principal photography on this picture was a shoot of about twelve weeks which ran from late 1974 to early 1975.
The movie is set in 1908 in Serenity, Colorado, USA.