The decisions they made that week in 1970 were destined to reverberate through the sporting world for many years to come.

“Will Olympism pay for the choices made in Amsterdam?”asked the Gazette de Lausanne. It turned out to be a prescient question.

When they arrived, IOC members were taken on excursions to the tulip fields, along Amsterdam’s waterways and even a visit to see the "marvellous" collection of Rembrandt’s paintings, but when IOC President Avery Brundage welcomed his colleagues to the session, his words were uncompromising.

“It is my painful duty to inform you that the Olympic Games are in trouble, in serious trouble. We need your help and I hope you will listen carefully."

On the agenda that week was the election of host cities for the 1976 Games.

The Olympic future of South Africa was also to be discussed.  The Reuters News Agency correspondent suggested this would be "the biggest headache."

In the Olympic Review, IOC director Monique Berlioux had written optimistically,  “we wish all those taking part every success in their work and may all their decisions be wise ones!”

Queen Juliana and Prince Bernhard gave a Royal welcome to the members and the Opening Ceremony was held at the RAI Conference Centre, which a few months earlier had staged the Eurovision Song Contest.

The main working Session was at the Esso Motor Hotel known as the “Essotel”.

Los Angeles were first to present their 1976 Olympic bid. Bid Committee President John Kilroy was there with Mayor Sam Yorty as part of a six man delegation. Their presentation included a film, relatively unusual in those days.

They were questioned about finance, television money and smog caused by heavy traffic.

Then came Montreal, led by Mayor Jean Drapeau, the driving force behind many municipal projects such as Expo’67.

Drapeau told the IOC members, "we made it with the Expo and will make it with the Olympics. If the city of Montreal promises to hold the Games, this promise is the most valuable guarantee."

Although Moscow was bidding for the first time, some considered them to be the favourites.  Mayor Vladimir Promislov was officially billed as  "chairman of the Moscow Soviet of working peoples deputies." He led off their presentation.

When the first round of voting was announced, Moscow were in the lead. This prompted the Soviet news agencies to report that Moscow had been awarded the Games. It was a mistake.

In the second round, the decisive vote gave Montreal victory by 41 votes to 28.

Veteran Swiss Olympic writer Frederic Schattler observed that "the IOC had expressed a wish to elevate Olympism above politics."

The TASS news agency offered a different interpretation claiming the result was "contrary to elementary logic and common sense."

An angry Soviet delegate complained that "the decision not to give the Games to Moscow did not seem to be helping the development of the Olympic ideal. The IOC think the organisation of the Olympic Games is the privilege of the western world.”

Voting irregularities were suggested by Sovetsky Sport which wrote “America gave their voices in support of Canada when the Summer Games were decided and got in return Canadian support when the destiny of the Winter Olympics was decided."

In fact, Moscow and Los Angeles both had their chance as Olympic hosts in the years which followed.

Mayor Drapeau was said to have worked out Montreal’s 1976 budget of $120million (£97.1million/€110.7million) on his kitchen table. In fact in the wake of Munich, security alone was to cost more than his original figure.

He later famously insisted "the Olympics can no more run a deficit than a man can have a baby."

Costs spiralled as building work was delayed by strikes and bad weather and eventually Montreal was believed to have cost $1.4billion (£1.13billion/€1.29billion). By the time everything was eventually repaid some 30 years later, this amount had almost doubled.

In those days, the Winter Games took place in the same year as the Games of the Olympiad. It was unintentionally symbolic that the orchestra had played a piece of music entitled the "Piet Hein Rhapsodie" at the Opening Ceremony.

Hein was a privateer who captured Spanish treasure from the "Silver Fleet" during the 17th century and became a Dutch folk hero.

Brundage had a different type of treasure in mind. A staunch defender of the amateur Olympic ideal, he had refused to attend Alpine skiing at the 1968 Grenoble Winter Olympics. He regarded skiers as professionals in everything but name and conducted a furious campaign against them.

He did enjoy one small victory in Amsterdam, a modification to the Olympic Charter which stipulated "the display of any clothing or equipment marked conspicuously for advertising purposes in any Olympic venue may result in immediate disqualification or withdrawal of credentials."

Nonetheless, he promised to "drop an atom bomb" in his speech and described "revolting scandals associated with Alpine skiing for the last 20 years."

In a Session where the next host city was decided, he spoke of the "startling result" of a referendum when only 40,912 citizens of Zurich were in favour of bidding for the 1976 Games.

There were 145,347 votes against.

"This indicates how far this disillusionment which menaces the future of the Olympic Movement has spread" said Brundage.

Switzerland did put forward Sion as a candidate. They were up against the Finnish bid from Tampere, Canada’s Vancouver-Garibaldi and Denver City from the United States.

Voting went to three rounds before Denver beat Sion 39-30.

"We will set an example to the youth of the world in staging a really amateur Winter Olympics at the lowest cost ever” insisted Denver Mayor William McNichols.

Yet within a year, there were objections to the budget at a state legislative council in Colorado.

An environmental group, called Protect our Mountain Environment was unhappy about the proposed location of the Nordic competitions.

Eventually a referendum was held. It delivered a resounding "no" and the Denver Olympic Committee were forced to hand back the Games.

The South African question was listed as item 23 of 24 on the agenda.

No athletes had competed at the Games for South Africa since 1960 but the South African Olympic Committee (SANOC) remained part of the Olympic Movement.

It was an era when many other nations on the continent achieved independence. A Supreme Council for Sport in Africa had been established. It wielded considerable influence throughout the continent.

In 1970 it was ready to strike. At a meeting in Cairo, other African nations, resolved to boycott the 1972 Munich Olympics if no action was taken against South Africa.

The official minutes of the IOC Session record that "the recommendation before the assembly was the withdrawal of recognition of SANOC."

Jean-Claude Ganga from the Congo joined Nigerian officials Abraham Ordia and Nigerian Olympic Committee President Henry Adefope to represent the other African NOCs as they set out the "case against."

“SANOC has never shown any independence towards its Government in the application of the policy of racial discrimination and segregation existing in its country” and that it was "in a position to resist the political pressures of its Government."

It pointed out that some ethnic groups were not permitted to affiliate to national sports federations in the country. The documents stated that SANOC "practices racial discrimination against African and other coloured sportsmen by failing into their duty to ensure their participation as full and equal members."

SANOC President Frank Braun then made his reply in which he described the accusations as a "hate campaign" and asked "why must sport in South Africa be the victim of a vendetta which may have merits for the ideological purposes of those behind it, but which certainly could not have the interests of the advancement of sport at heart? Only blind prejudice would deny the progress that has been made.”

His words did not go down well. When the vote came, South Africa were expelled by a majority of 35-28, though three members abstained.

South Africa’s IOC member Reg Honey offered to resign, but Ordia sent a note to IOC President Brundage.

"I would respectfully request you to appeal to Mr Honey to reconsider his decision. It is our wish that he continues in order to maintain the link with the Olympic Movement and the youths of South Africa" wrote Ordia.

Honey duly remained until his death in 1982.

In 1970, he was joined on the IOC by Maurice Herzog of France, Sven Thofelt of Sweden and Henry Hsu from Taiwan.

The appointment of Hsu proved controversial.

"Hsu’s nomination was unanimously opposed by the IOC executive but Brundage ignored us and Hsu became a member" wrote Lord Killanin in his memoirs.

Like so many decisions taken at that Session in Amsterdam, it had repercussions. At the height of the "two China" dispute in the late 1970s, Hsu actually sued the IOC.