The novel was based upon rumours and speculation following the 1968 landing of a mysterious aeroplane in Rhodesia that was said to have been loaded with mercenaries and "an African president" believed to have been a dying Moïse Tshombe.

Allen Faulkner, a former British Army colonel turned mercenary, arrives in London to meet merchant banker Sir Edward Matheson.

The latter proposes an operation to rescue Julius Limbani, the imprisoned President of a southern African nation who is due for execution by General Ndofa.

President Limbani is held in a remote prison in Zembala, guarded by a regiment of General Ndofa's troops known as the "Simbas".

After Faulkner convinces Janders, they decide to hire another old friend of theirs, former former Irish Guards Lieutenant and pilot turned smuggler Shawn Fynn.

Fynn also brings in Pieter Coetzee, a former soldier in the South African Defence Force who wishes only to return home and buy a farm.

Back in London, however, Matheson cancels the extraction flight at the last moment, having secured copper mining assets from General Ndofa in exchange for President Limbani.

The mercenaries make their way to Limbani's home village, hoping to start a rebellion, but understand that his people are too ill-equipped to fight.

As the Simbas close in, the mercenaries suffer heavy casualties holding them off in a climactic battle while Fynn starts the Dakota's engines.

The thirteen surviving mercenaries from the original fifty eventually manage to land at Kariba Airport, Rhodesia, but Limbani dies from a gunshot wound sustained during the escape, ultimately rendering the entire mission a failure.

[7] Likewise, the character of Julius Limbani, the deposed pro-Western leader who was imprisoned following the hijacking of an airliner was based upon Moïse Tshombe.

[7] Like Faulkner, Hoare was a former British Army officer living in South Africa who worked as a mercenary and had been hired to fight for the Tshombe government in the Congo in 1964-1965.

[7] Although Lloyd had both Richard Burton and Roger Moore in mind for their respective roles from a relatively early stage, other casting decisions were more difficult.

As the mercenaries were mostly composed of military veterans (some of whom had fought under Faulkner's command before), it was necessary to cast a number of older actors and extras into these physically demanding roles.

Northern Irish actor Stephen Boyd, a close friend of Lloyd's, was originally set to star as Sandy Young, the sergeant major who trains the mercenaries before their mission.

[4] Lloyd had offered the part of the banker Matheson to his friend Joseph Cotten, but scheduling difficulties meant that he also had to be replaced, this time by Stewart Granger.

Burt Lancaster originally hoped to play the part of Rafer Janders who in Carney's book was an American living in London.

Lloyd initially had reservations about casting Harris because of his wild reputation – he was blamed for Golden Rendezvous going over budget by $1.5 million due to his drinking and rewriting the script.

Percy Herbert, who played the role of Keith, was a veteran of World War II, in which he had been wounded in the defence of Singapore, then captured by the Imperial Japanese Army and interned in a POW camp.

Palitoy based the figure "Tom Stone" (part of the Action Man team) on the character Blake after looking at the pre-production photos and posters of the film.

Susan Hunt, Richard Burton's wife at the time of filming played an Egyptian Girl flirting with Col. Faulkner.

Roger Moore estimated location filming in Africa took about three months with the unit taking over a health spa near Tshipise in Northern Transvaal (now Limpopo); shooting also took place at Messina Border Region.

The rugby scenes were filmed over a period of two days at Marble Hill Park in Twickenham with extras drafted in from nearby Teddington Boys' School.

[15] South Africa was subjected to a mandatory arms embargo imposed by the United Nations Security Council Resolution 418 in 1977.

All three pieces are included on the soundtrack album, as well as the song "Dogs of War" that featured lyrics sung by the Scots Guards to Budd's themes.

The Wild Geese enjoyed a Royal premiere in support of Scope, with most of the stars of the film present along with John Mills.

Warned of the protest, producer Lloyd brought copies of newspaper articles describing the film's premiere in the black township of Soweto, where it had been received with enthusiasm and approval.

[27] In a later interview actor Hardy Krüger complained about how his character was portrayed in the film: For this kind of a delicate story in Africa with an element of battle in it, there has to be some shoot-out.