Filmed in Siena and other locations in Tuscany. Opened in Paris in December 1962 as Le mercenaire; running time: 92 min; alternative French running time: 100 min. Italian titles: Lo spadaccino di Siena and Il mercenario. French and Italian sources credit Bandini as director; Continenza and Fabre as screenplay writers; and Rustichelli as composer of music. U. S. sources credit Prier as director; Michael Kanin, Fay Kanin, Coppel, and Marshall as writers; and Nascimbene with music.