A demand from the local teachers' union for better pay in May escalated into a full-scale mobilisation after governor Ulises Ruiz Ortiz, better known by his initials URO, refused to negotiate.
In London's West End, a loud and lively picket of the Mexican embassy caught the attention of many passersby. To the background of banners and placards reading "Free Oaxaca," samba band Rhythms of Resistance brought a tropical beat to the grey rainy streets.
Many Mexicans were present, some traveling from Cambridge, Norwich and Manchester to attend the picket.
Campaigners then regrouped at the National Union of Journalists headquarters in King's Cross, where left MP Jeremy Corbyn spoke about the urgent need for solidarity with the Mexican people.
The veteran activist politician, who is tipped to become foreign secretary if John McDonnell succeeds in his Labour party leadership bid, explained how left-wing presidential hopeful Andres Manuel Lopez Obrador (AMLO) was robbed of the top job by ruling party candidate Felipe Calderon.
Mr Corbyn pointed out that AMLO had been a popular, progressive mayor of Mexico City and "ensured the construction of 44,000 council homes - which is 44,000 more than were constructed in this country during the same period."
He described the million-strong national democratic convention that he attended in September, at which it was "decided that, today, November 20, AMLO should be inaugurated as the real president of Mexico. And that is exactly what is happening this evening."
A short film direct from Oaxaca was then screened, in which activists explained how the conflict had developed, making it clear that they would not back down until governor URO resigned.
The film was followed by a heated but comradely debate about the best way to take the solidarity movement forward.
After a discussion over aims and priorities, a solidarity committee was formed to help coordinate future actions and build a network of support.
It was unanimously decided to hold another picket during Calderon's upcoming inauguration - which AMLO supporters have vowed to obstruct - on Friday 1 December, followed by a fund-raising social event.
Those present also agreed to draft trade union resolutions and launch a press campaign to break the media silence on the issue.
Argentina Solidarity Campaign spokeswoman Alejandra Rios, who proposed the idea of a committee, made clear the determination of everyone present.
"This is just the beginning of the campaign," she insisted.
"We are committed to support the people of Oaxaca's human rights, which are being violated, and we join in with their demand that URO must go."
A spokesman for Hands Off Venezuela, which had voted to sponsor the day's events at its annual conference two weeks ago, agreed.
"We must now put as much pressure on the Mexican and British governments as possible to resolve this issue without further bloodshed," he said.
"The will of the people must be respected."