Ten months before her dramatic defenestration, Margaret Thatcher bathed in warm applause greeting her address to the Board of Deputies. The speech contained her usual mix of paeans to the values of the Jewish community and praise for the state of Israel.

The Prime Minister also briefly mentioned her Jewish constituents in Finchley. “I am very pleased to note,” she joked, “that the majority there seem to hold my views on very many things.” Certainly, her three decades representing the north London seat and the results of the general election three years previously seemed to bear that out. As she won a then historic third term in Downing Street, Finchley’s Jews approved, with polls finding six out of 10 backing her.

But the relationship between the Prime Minister and the Jews of Finchley was not without its trials. On two occasions — in 1964 and 1974 — she appeared perilously close to defeat at the hands of Jewish voters.

When Mrs Thatcher was selected as Finchley’s Conservative candidate in July 1958, she inherited a seemingly impregnable majority of nearly 13,000. She soon discovered, however, that the Tories had a little local difficulty on their hands. At its centre were the constituency’s Jewish voters who constituted a politically significant one-in-five of the electorate. It stemmed from that most quintessentially middle-class of pursuits: golf. The previous year, a number of Jews — including Shirley Porter, then a young Liberal activist — had applied to join the Finchley golf club. Each had had their membership refused; not an uncommon occurrence at golf clubs at this time.

The club leased its land from the Tory-dominated borough council, and its officers included a number of prominent local Conservatives. Scenting an opportunity, two Jewish Liberals fought and won seats in Finchley’s wealthiest and most Jewish wards. Upon her selection, a horrified Mrs Thatcher discovered that, while the club had swiftly caved in and agreed to admit Jewish members, more lasting damage had been done: in the next year’s local elections, the Liberals made further advances. “The Jewish faith,” she worriedly wrote to Central Office, “have allied themselves to Liberalism.”

The golf-club scandal had come to symbolise a cloud of antisemitism which hung over the local Tory association. That was not altogether surprising given the attitude of Sir John Crowder, the retiring MP, who privately grumbled that the national party was trying to impose a choice between “a bloody Jew and a bloody woman” as his successor.

Mrs Thatcher was, she later recalled, upset that her new local association had been “tainted” by antisemitism and moved swiftly to repair the damage. She prioritised the recruitment of new Jewish members and invited Sir Keith Joseph, the Tories’ rising Jewish star, to speak locally. Her efforts appeared to bear fruit: in October 1959, she increased the Tories’ majority to over 16,000. However, the Liberal bandwagon continued to roll. In 1962, the party made sweeping gains and a year later it seized control of Finchley town hall. Six of its 19 councillors were Jewish, including the new leader of the council and mayor. Drawing a parallel with the Liberals’ recent dramatic by-election victory, the press dubbed Finchley “the Orpington of North London.”

Mrs Thatcher knew exactly the source of her problems. “It’s the golf club… that’s where it all started,” she told one journalist. Her finely tuned political antenna were correct: she held Finchley in 1964, albeit with a sharply reduced majority. However, Jews in the seat voted Liberal in considerably higher proportions than non-Jews, with Mrs Thatcher and the Liberal candidate, John Pardoe, each taking roughly 40 percent of the Jewish vote.

A decade later, Mrs Thatcher found her position locally once again under threat. This time, however, it wasn’t the putting greens of Finchley, but a conflict in the Middle East which was the source of her woes.

Ted Heath’s Cabinet, in which she served as Education Secretary, had responded to the Yom Kippur assault on Israel in October 1973 by imposing an arms embargo on both aggressor and victim. It was, as the future Foreign Secretary, David Owen, put it, “the most cynical act of British foreign policy since Suez”, designed to salvage the government’s teetering economic policy from the threat of an Arab oil boycott.

In the Commons, the Labour leader, Harold Wilson, raised the spectre of appeasement and likened Heath’s stance to Britain’s policy of non-intervention in the Spanish civil war. Wilson’s motion condemning the embargo was, however, defeated.

Among those toeing the government line was the honourable member for Finchley.

Throughout north London feelings ran high. Posters of Golda Meir appeared in the windows of Jewish homes and synagogues set up blood banks to provide Israel with much-needed supplies, while charismatic rabbis such as Leslie Hardman in Hendon and Saul Amias in Edgware rained down righteous anger on the government. Eight Jewish Tory councillors on Barnet council condemned the embargo as “morally wrong”, while John Gorst, Mrs Thatcher’s Conservative colleague in neighbouring Hendon North, led the rebellion against Heath, attacking the “oily blackmail” of the Arab states.

At a protest meeting attended by 200 people, the Finchley Anglo-Israel Friendship League, of which Mrs Thatcher was president, unanimously passed a resolution urging full “diplomatic and political support” for Israel. Called to an emergency Cabinet meeting, Mrs Thatcher sent a message to the Friendship League vowing to oppose the embargo. Behind closed doors at No.10, she, Joseph and Lord Hailsham fought a losing battle. Thatcher argued that it was unseemly for Britain to ignore the aggression against Israel simply because of “our oil supplies” and warned of a political backlash.

She was to feel that backlash herself when Heath called a snap election four months later. Amid the chaos of the miners’ strike and three-day week, Mrs Thatcher’s vote to uphold the arms embargo came back to haunt her. Her “betrayal of Israel”, warned the young, Jewish Liberal candidate, Laurence Brass, would be at the centre of his campaign. By polling day, Brass appeared set to pull off a shock victory: ITV invited him to appear on its post-election results programme.

In the end, Mrs Thatcher survived: her majority whittled down to under 6,000. Even allowing for the national Liberal surge, she — like other Tories who had failed to oppose the embargo — appeared to suffer particularly badly at the hands of Jewish voters.

Despite occasional rifts and rows, the Jewish community has rarely had a greater admirer, or Israel a closer friend, than Margaret Thatcher. As Prime Minister, civil servants in the Foreign Office would sneeringly refer to her support for Israel as deriving from “the Finchley factor”. In truth, the relationship was both deeper and more complex than either her critics or admirers would care to admit.

Robert Philpot’s ‘Margaret Thatcher Honorary Jew: How Britain’s Jews Helped Shape the Iron Lady and Her Beliefs’ is published by Biteback on June 29