The original screenplay was titled Chisum and the Lincoln County Cattle War, as stated in a 12 Aug 1969 DV brief. The film marked John Wayne’s 200th starring role in a feature motion picture, according to an article in the 25 Jan 1970 LAT, which also noted that Wayne had just made the list of “Top Ten Money-Making Stars” for his twentieth consecutive year. At the time, he was said to be ranked number two behind actor Paul Newman.
       Chisum was announced as Wayne’s next project in the 19 May 1969 DV. Twentieth Century-Fox Film Corp. was initially set to finance and distribute, but the 6 Aug 1969 Var indicated that the film had moved to Warner Bros.-Seven Arts, Inc. The shift reportedly occurred because Wayne was eager to begin filming in 1969, while Fox’s production slate for the year was already full.
       A news brief in the 10 Jul 1969 DV stated that Wayne wanted actor Bruce Cabot, who had recently lost forty-five pounds to star in WUSA (1970, see entry), to gain back twenty-five pounds for the role of “Sheriff Brady.”
       Months prior to the 6 Oct 1969 start of principal photography in Durango, Mexico, director Andrew V. McLaglen and Wayne had collaborated on The Undefeated (1969, see entry), also shot in Durango. Although local vendors had allegedly gouged prices during that shoot, the 26 Aug 1969 DV noted that McLaglen and Wayne had agreed to return with Chisum after Durango’s governor had made a personal promise of better treatment. An item in the 17 Sep 1969 Var noted that Wayne’s son, executive producer Michael Wayne, laid the cornerstone of a new $1.6 million filming complex, financed by the state of Durango, where shooting was set to take place. The budget for Chisum, which was scheduled for an eleven-week shoot, was cited in the 1 Oct 1969 Var as $4.8 million.
       A 24 Jun 1970 world premiere was planned in Dallas, TX, the 17 Jun 1970 Var reported. Wayne and several co-stars were set to attend the event, in addition to “two days of pre-opening festivities.” The 24 Jun 1970 Var noted that Wayne would receive the American Academy of Achievement’s “Golden Plate Award” on the night of the premiere, and Texas governor Preston Smith was also scheduled to present the actor with a Winchester rifle after a parade through downtown Dallas.
       Chisum grossed $6 million in domestic film rentals, making it the nineteenth-highest-grossing American release in 1970, according to a box-office chart in the 6 Jan 1971 Var.
       Items published in DV, Var and LAT between 19 Aug 1969 and 24 Nov 1969 listed the following actors as cast members: Rudy Diaz; Pedro Gonzalez-Gonzalez ; Enrique Lucero; Jose Angel Espinosa; Enrique Villa (son of famed revolutionary Pancho Villa); Hank Worden; Eddie Donno; and Jim Burke. A 23 Oct 1969 DV brief also noted that Andrew V. McLaglen’s children, Josh and Mary, would make their motion picture acting debuts in Chisum, and the 2 Dec 1969 DV stated that Mexican singer Alida Andrade would record two songs for the picture.
       Mexican set designer Ramon Rodriguez Granada died while being flown back to Mexico City, Mexico, from the set in Durango, where he had been working on the picture, according to a notice in the 22 Oct 1969 Var.