Mercenaries of the Rio Grande (1965) is a Adventure, Western film that follows dr. Karl Sternau, the personal physician of the count Bismarck, who spent much of his youth in Mexico, is sent back to that country during the occupation by French troops in the service of the Austrian 'Emperor' Maximilian, to carry an encouraging letter from U.S. President Lincoln to the nationalist Mexican president Benito Juarez. Mercenaries of the Rio Grande is not currently listed with streaming providers in your selected region, but availability can change over time. It has a user rating of 5.9 out of 10 from 34 votes. Fans of adventure movies may also want to explore similar titles below.