The plot to target an EDL rally in Dewsbury, West Yorkshire, in June last year only failed by chance, and the six conspirators would have gone on to attack another rally by the far right group had they not been stopped, the Old Bailey was told.
Leader Tommy Robinson and his deputy Kevin Carroll briefly went into the public gallery of Court 12 to watch the beginning of the hearing.
Barriers had been erected in the street outside the building amid a heightened police presence.
Members of the far-right group were encouraged to attend Thursday's sentencing via the group's Twitter feed and Facebook page.
EDL demonstrators gathered at the police pen at lunchtime, chanting: "Anjem Choudary, off our streets," referring to the radical preacher.
With English flags on display, they chanted "EDL", while one called to the gathered police: "Old Bill, do your f****** job."
On Wednesday graffiti saying ''EDL'' was found daubed at a Somali community centre in Muswell Hill, north London, which was destroyed by fire.
The blaze is being investigated by counter-terrorism police. The EDL has denied any involvement.
Inside the court, prosecutor Bobbie Cheema QC said: "In the months leading up to June 30, 2012 these six men, all ideologically committed to radical Islam, planned to execute a terrible vengeance on the English Defence League for what they perceived to be the EDL's recent blasphemous words and actions against the Prophet Mohammed and Islam.
"Their plain and now admitted intention was to carry out a terrorist attack using a varied selection of offensive weapons: an improvised explosive device, two sawn-off shotguns, swords and knives.
"As well as members of the EDL and police officers on duty, ordinary shoppers and workers would have been in the town centre at the time of the rally, at the time of the planned attack."
All of the men except Hasseen travelled to Dewsbury on the day of the rally but arrived at around 4pm, while the event had finished earlier than expected at 2pm.
They were armed with two shotguns, swords, knives, a nail bomb containing 458 pieces of shrapnel, and a partially assembled pipe bomb.
The nail bomb was an 18in rocket stuffed with shrapnel and was to be powered by explosives taken from at least two large fireworks.
Ms Cheema told the court: "The defendants have admitted what is obvious from the evidence gathered during the careful police investigation: that they intended to bring about a violent confrontation with the EDL during which they intended to use weapons to cause serious injuries and they anticipated, each one of them, that some victims may have died.
"It takes but a little contemplation to realise that had the retaliatory attack gone ahead as planned it would have had a powerful impact on relations between different groups who for the most part live peacefully alongside each other in the UK and that impact would probably have still been reverberating today.
"There can be little doubt that a violent attack of the kind intended to be carried out would have been bound to draw a response in revenge from its target and most likely would have led to a tit-for-tat spiral of violence and terror. The defendants anticipated as much."
She added: "The plan was only averted because the rally finished earlier than expected and the crowd had dispersed by the time the defendants arrived.
"Importantly, although this particular attack was averted there is no reason to doubt that had they not been caught, these six men would have pursued their aim of retaliation and proceeded to carry out their plans on a subsequent occasion."
The court heard that the plotters took 10 copies of a document entitled "Operation: In defense (sic) of the Prophet Muhammad".
The hate-filled note was addressed to the enemies of Allah and his messenger and referred to the Queen as the "kafir (non-believer) female devil".
At earlier hearings it was revealed that the note said: "This is a message to the enemies of Allah and his messenger. This is a message to the kafir (non-believer) female devil and self-proclaimed Queen Elizabeth and her accursed jubilee, fooling a nation of blind sheep to your self-proclaimed royalty and majesty."
The document addressed the EDL directly, saying: "To the EDL (English Drunkards League). O enemies of Allah! We have heard and seen you openly insulting the final Messenger of Allah... you should know that for every action there is a reaction.
"Today is a day of retaliation (especially) for your blasphemy of Allah and his Messenger Muhammad. We love death more than you love life. The penalty for blasphemy of Allah and his Messenger Muhammad is death.
"What we did today was a direct retaliation of your insulting of the Prophet Muhammad (peace be upon him) and also in retaliation of your crusade against Islam/Muslims on a global scale. It is of the greatest honour for us to do what we did.''
Today the Old Bailey was told that the six men, who are all from the West Midlands, met at the Darul Ihsaan Islamic and Fitness Centre in Birmingham, known as the Baker Street gym, on the day before the planned attack.
Hussain worked at the gym, while all the other men except Saud were members.
Details of extremist material the men had in their possession were also read to the court.
Khan had a green A4 notebook in his bedroom with "This belongs to Omar Khan so don't touch" written on the cover, which contained passages suggesting jihad is an obligation.
Prosecutors claim Hasseen was the most "ideologically committed" of the group, and he was found to have 859 files containing extreme material. Ahmed had 203, while Saud possessed 75.
Uddin had material including a number of Islamic chants interspersed with gunfire stored on his phone, and Hussain had a lecture in which the speaker said: "Oh God please blow me up."