The Cardiff man accused of carrying out the Finsbury Park attack has gone on trial at Woolwich Crown Court in London.
Darren Osborne, 48, allegedly mowed down Makram Ali, 51, and nine other people in a north London street which was busy with worshippers attending Ramadan night prayers in June last year.
Osborne, of Glyn Rhosyn, in Cardiff, has denied charges of murder and attempted murder.
Prosecutor Jonathan Rees QC said Osborne was trying to kill 'as many of the group as possible' when he drove a heavy box van into Muslims gathered at the junction of Seven Sisters Road and Whadcoat Street.
Mr Rees said the defendant had driven from Cardiff to London the previous day, originally intending to drive the van into people taking part in the Al Quds Day march, but began looking for another target when this did not prove viable.
Mr Rees then read out a handwritten note found in the cab of the van within hours of the attack, which complained about terrorists on the streets and the Rochdale child exploitation scandal.
The note read: 'This is happening up and down our green and pleasant land.'
The court heard that the defendant's partner, Sarah Andrews, described him as a 'loner and a functioning alcoholic' with an 'unpredictable temperament'.
She said Osborne had become 'obsessed' with Muslims in the weeks leading up to the incident after watching the BBC drama Three Girls, which was based on the true stories of victims of the Rochdale grooming gangs.
Mr Rees said it appeared to Ms Andrews that he was becoming brainwashed, and with the benefit of hindsight she described him a 'ticking time-bomb'.
During the weekend prior to the attack, Osborne was heard 'preaching racial hatred' in a pub by Callum Spence, a soldier serving with the Royal Engineers.
Speaking with 'passion and anger', he is said to have told the soldier: 'I'm going to kill all the Muslims, Muslims are all terrorists. Your families are all going to be Muslim. I'm going to take it into my own hands.'
The court heard that the defendant had driven around London looking for mosques, stopping near the Blackhall Tunnel to ask a motorist for directions to Finsbury Park.
The driver allowed the defendant to follow him and he arrived in the Finsbury Park area at just before 11.30pm.
Mr Rees said he then approached people and enquired about the whereabouts of the Finsbury Park Mosque or "the big Mosque", claiming there was going to be a protest there.
Jurors were played CCTV footage of victim Makram Ali collapsing shortly before a van drives into the group which had flocked to his aid.
In the footage, a white van can be seen turning sharply off the road, mounting the curb and ploughing into the group of people, some of whom later spill on to the adjacent bus lane as they attempt to pin down the driver.
Several of those who went to help Mr Ali said he was "definitely alive" and conscious in the moments before being struck.
One male, who cradled Mr Ali's head, said he started mumbling before saying more clearly that he just wanted to go home and had attempted to get up.
Following the incident, a number of men tried to prevent the driver's escape and keep him pinned to the ground as he was heard to say "I want to kill more Muslims", Mr Rees continued.
Another man in the group remembered the defendant - who was "constantly smiling" after he had been detained - saying: "I've done my job, you can kill me now", he said.
Osborne initially claimed he had lost control of the van and had drunk a couple of pints, but a road-side breath test showed no alcohol in his system, Mr Rees said.
The trial, before Mrs Justice Cheema-Grubb, is expected to last two weeks.