George Galloway, the Workers’ Party leader and newly-elected MP for Rochdale, has campaigned ferociously against Israel, its friends and allies for many decades, having once told an interviewer that he had decided to “devote the rest of my life to the Palestinian and Arab cause” after a visit to Beirut in 1977.

Since losing his last seat in Parliament in 2015, that has meant working for the Iranian TV channel Press TV, which was banned from broadcasting in Britain in 2012 by the regulator Ofcom, and presenting shows on the pro-Putin Russian channel RT.

But tempting as it may have been to see him thus as a marginal figure, reduced to operating on the wilder political fringe, Galloway has proven time and again that he has a limitless appetite for staging comebacks, and the capacity to wreak havoc — especially for the Labour Party. He is now set to do so again.

It is not a surprise that Jewish organisations have reacted to Galloway’s win in Rochdale with dismay. A brutal political pugilist, he can be expected to use his renewed platform in the Commons to attack Israel and those who support it at every opportunity.

Previous examples of his anti-Zionist rhetoric would fill a sizeable book. But his comments include a pledge in a speech in 2014 to make Bradford — where he occupied a parliamentary seat for the period 2012-15 after winning another by-election — “Israel free”.

By this, he went on, he meant: “We don't want any Israeli goods, we don't want any Israeli services, we don't want any Israeli academics coming to the university or the college, we don't even want any Israeli tourists to come to Bradford, even if any of them had thought of doing so.

"We reject this illegal, barbarous, savage state that calls itself Israel. And you have to do the same.”

In January this year, shortly before the Rochdale seat became vacant with the death of the Labour incumbent Tony Lloyd, Galloway posted on X (formerly Twitter) that “Gaza is a concentration camp and the guards are murdering the captives, women and children first. Nothing complicated about it. You are either with the Gaza genocide or you are against it.”

According to the Campaign Against Antisemitism, he recently described the October 7 atrocities as a “concentration camp breakout”, and Hamas terrorists as “fighters”.

Following Galloway’s win, his party’s deputy leader, the former Labour MP Chris Williamson, refused to condemn the October 7 massacre. Speaking on Radio 4, he said: “You can't expect to live in a situation where a people have been oppressed for 75 years and not expect a reaction,” and claimed most of the victims of the atrocities had been killed by the IDF.

Having won his victory, Galloway left the Labour leadership in no doubt as to the pain it can expect in the run-up to this year’s general election in constituencies where, as in Rochdale, there is a high proportion of Muslim voters.

“Keir Starmer — this is for Gaza,” Galloway said. “And you will pay a high price, in enabling, encouraging and covering for, the catastrophe presently going on in occupied Palestine in the Gaza Strip.”

Later he added: “I think Keir Starmer has woken up this morning to his worst nightmare.”

Labour insisted Galloway only won "because Labour did not stand”, having been forced to suspend its candidate Azhar Ali after he was recorded saying that Israel had let its defences drop deliberately on October 7 to create a pretext for invading Gaza. Its deputy campaign co-ordinator Ellie Reeves said: “George Galloway is someone who stokes up division and fear. This isn’t how we would have wanted this by-election to play out.”

Galloway’s involvement in the Arab and Palestinian “cause” dates back to 1980, when as a rising Labour activist, he campaigned successfully to fly the Palestinian flag from Dundee town hall, and arranged for the city to be twinned with Nablus in the West Bank.

Having first won his first parliamentary seat for Labour in 1987, Glasgow Hillhead, he became an increasingly outspoken critic of the party’s leadership. He opposed the 1991 Gulf War triggered by Iraq’s invasion of Kuwait, claiming the tiny oil-rich kingdom had been “stolen from its motherland”.

In 1994, Galloway visited first Gaza, then Saddam Hussein in Iraq. By this time, the dictator had gassed thousands of Iraqi Kurds, and was running one of the world’s most brutally oppressive regimes. Yet Galloway told him: “Sir, I salute your courage, your strength, your indefatigability ... I can honestly tell you that there was not a single person to whom I told I was coming to Iraq and hoping to meet with yourself who did not wish me to convey their heartfelt, fraternal greetings and support.”

He met Saddam again in 2002, claiming that he went to try to prevent the war that started the following year by persuading him to give UN weapons inspectors full access. He later said he regarded him as a “bestial dictator”, but was opposed to using force to eject him from power.

Galloway was expelled by Labour in 2003 when he said that British troops serving in Iraq should refuse to obey orders on the grounds that war against the Iraqi dictator was “illegal”.

He went on to lose his Glasgow seat when it was abolished by boundary changes in 2005, but his first comeback started immediately. Standing as the candidate for the Respect Party, which Galloway had founded, he defeated the Labour minister Oona King in what had been a longstanding Labour stronghold in east London, Bethnal Green and Bow.

The constituency, once heavily Jewish, has a high proportion of Muslim voters, and Galloway claimed that Labour had been waging a “war on Muslims”. In 2010, the Channel 4 Dispatches programme broadcast a secret recording in which Galloway said the Islamic Forum of Europe, which advocated sharia law, had played a “decisive role” in his victory.

He won his next seat, Bradford West, another constituency with a large Muslim population, at a by-election in 2012. He described his success as “the most sensational victory in British political history”, but lost the seat at the general election three years later.

But if Jeremy Corbyn had won the elections held in 2017 and 2019, Galloway would have been close to the centre of power, through his close friendship with Corbyn’s strategy chief Seumas Milne. The pair are said to have spoken every day for many years.

In that scenario, his influence on Labour would have been direct. But his victory in Rochdale now may make almost as great an indirect impact. Starmer’s vulnerability to losing Muslim votes over his stance on Gaza is now front and centre of British politics, and the new Member for Rochdale is certain to ensure that nobody ever forgets it.