Now, having persuaded the French to join them in calling in the English bluff by announcing plans for a Four Nations tournament, the Five Nations is on the point of disintegration.
The steely brinkmanship that the Celts had shown may, at first sight, seem simply about Celtic resentment of overbearing Anglo-Saxons. However, while that ingredient has hardly been in short supply, the root of the conflict goes far deeper. It is about who holds the reins of power in global rugby.
It is no coincidence that Vernon Pugh, one of the key figures in this administrative battleground, doubles as chairman of both the International Board and the Welsh Rugby Union.
The IB has the stated aim of spreading the rugby gospel. Part of its mission is to see the game broadcast to the widest possible global audience - most of which receives its pictures from terrestrial rather than satellite television. Hence the successful underwriting of the 1991 and 1995 Rugby World Cups, with increasingly lucrative terrestrial television contracts reaching a massive audience.
The 1995 World Cup was broadcast in 124 countries, with only the football World Cup, the Olympics and the world athletics championship being received by more countries.
The IB consequently views with suspicion any substantive move to a satellite company like Sky. Their concerns are twofold. First, satellite television has a much smaller global audience. Second, it could pose a threat to the World Cup.
Should Sky succeed in lining up the Five Nations alongside their Tri- Nations (Australia, New Zealand and South Africa) rights, they will have secured rugby's two biggest annual events. The IB's fear is the control that would be handed to Sky in the running of the game. Their main concern is that the World Cup could be undermined because the commercial appeal of annual north-south world championship play-offs would prove too tempting for Sky. Another big worry is that Sky would try to force a union-league hybrid to link with their Super League venture.
A glance at the IB's Oval World quarterly earlier this year would have provided Pugh's RFU opponents with an instructive insight into his agenda.
Television, Pugh said, must not be allowed to insist on wall-to-wall rugby, nor tamper with the laws for the sake of quick-fix entertainment. "There is the danger of the ethos being polluted, that is why we must be strong managers. We have to stand up to those aggressive commercial concerns who want to put money solely in the pockets of the few," Pugh said.
Furthermore, as befits a QC, Pugh's marshalling of the arguments against the RFU's call for a greater share of the Five Nations proceeds has been astute. Both he and Tom Kiernan, the president of the Five Nations Committee, have argued that the Five Nations is a joint property to be shared equally, irrespective of the RFU's "more mouths to feed" theory. "If you followed that line of argument, where would it put New Zealand with their population of 3 million if they were in the Five Nations? Yet has anyone yet made a greater contribution to world rugby?" Kiernan said.
Another RFU tactic that came under fire was the attempt to equate England's pounds 87.5m go-it-alone bid with French rights to sort out their own television contract. Kiernan said the two were totally different: "Unlike England, the French were never part of the four home unions, they were never involved in Lions tours, they had separate incoming tours agreements, and they have only been members of the IB since 1979. They also happen to have a different culture and language."