A number of both pro- and anti-Robinson demonstrators gathered outside the court, creating a febrile atmosphere as they waited for the verdict, with confrontations with the police and smoke bombs being let off.
Police were then pelted with cans and plastic bottles as the group began chanting "we want Tommy out".
In her ruling, judge Victoria Sharp said that in his video Yaxley-Lennon, who argued he is highlighting cases ignored by mainstream media, "approves and encourages vigilante action" and his viewers would have understood it as "an incitement to engage in harassment of the defendants".
The judge said the content of the video "gave rise to a substantial risk that the course of justice in that case would be seriously impeded" and the confrontation of the defendants was a direct interference with the course of justice.
Upon his arrival at the court alongside right-wing commentator Katie Hopkins, Robinson told Sky News he was "being sent to jail for doing what you do" and that his impending sentence was "illegal".
He had been found to have committed contempt of court in a retrial by Dame Victoria Sharp and Mr Justice Warby at the Old Bailey, for filming and livestreaming the defendants in a child grooming case in 2018.
He was jailed for 13 months after being found in contempt of court on the day of the broadcast and served two months in jail but was freed after the original finding of contempt was overturned by the Court of Appeal in August 2018.
- What is contempt of court?
The impact the live streaming nearly allowed the groomers to walk free from conviction at Leeds Crown Court, It had such a serious impact on proceedings that the legal proceedings were nearly dropped.
Time served will be discounted, however, meaning Robinson should eligible for automatic release on licence after roughly two months.
But the case was referred back to Attorney General Geoffrey Cox, whose decision to cite public interest in bringing fresh proceedings against Robinson was approved by High Court judges back in May.
Contempt of court laws exist to ensure people get fair trials. The idea is that juries must not be influenced by anything but the evidence they hear in court.
British far-right activist Tommy Robinson was sentenced again to prison Thursday after being found in contempt of court, sparking clashes between police and his supporters in London. Proceedings become "active" when a suspect is arrested.