He might easily be described as the Marmite of the Jewish world: a communal gadfly who has garnered love and hate in almost equal parts, and almost certainly the only one ever to attract a multi-million dollar lawsuit from a global Jewish body (the World Jewish Congress).

Now the writer and historian Suzanne Rutland has produced a mammoth work, Lone Voice, appropriately subtitled The Wars of Isi Leibler, a detailed account of the life and battles of the religiously observant Australian businessman, drawing on Leibler’s own prodigious personal archives and numerous interviews with his protagonists.

Lone Voice chronicles, in at times suffocating detail, the trajectory of the Antwerp-born Leibler, who made his fortune in the travel business in Australia, and made his name in his early feisty campaigning for Soviet Jewry.

From 1978 to 1995 he was the acknowledged leader of the Australian Jewish community. But, as Suzanne Rutland records, along the way Leibler managed to have fights with many political “enemies”, including his own brother, Mark Leibler, who headed the State Zionist Council of Victoria in Melbourne, while Isi Leibler ran the Executive Council of Australian Jewry (ECAJ).

As the Australian Jewish News noted in 1982: “It was not a problem that required an organisational fix. The two sides warred bitterly over policy and about how to put forth the views of the community. The strife undermined ‘the effectiveness of what should have been concerted efforts for the cause of Israel and local communal representation’”.

Leibler’s campaigning for Soviet Jewry gave him his first steps onto the world stage, as he secured the ear and attention of a succession of Australian politicians. It is anyone’s guess whether Leibler was using the Australian political establishment, or the Australians using the diaspora Jew in their search for global influence in the 1960s. Australia’s very remoteness from world decision-making centres sometimes led to a “Wild West” situation in which the country was too often dismissed as negligible.

Whichever it was, Leibler’s near ubiquity in Jewish communal life soon brought him to the notice of Israeli leaders. Rutland indicates that Leibler acted as a backstairs conduit between successive Israeli governments and the Soviet Union in his efforts to free Soviet Jewry.

And meanwhile, Israel used Leibler and his travel connections to foster relations with China and India.

Rutland writes: “In the late summer of 1978, Isi was in the capital of the Soviet Union —his first visit — seemingly to lay the groundwork for Jetset’s role as Australia’s official travel agency for the 1980 Summer Olympics in Moscow.

“Back in Melbourne, meanwhile, Isi’s activities in the USSR left many people perplexed. They could not understand why the same man who had developed and spearheaded the Soviet Jewry movement in Australia was now doing business with the Kremlin, and why he was opposing calls for an international Olympic boycott. Was this the behaviour of a staunch anti-communist? Was he only interested in money?

“What Isi’s critics did not know was that he was clandestinely coordinating his moves with Israeli authorities and leading Soviet Jewry campaigners — the reason he traveled to Moscow via Jerusalem and London. At the time, Israel opposed boycotting the games, as did the refuseniks on the ground; the games were a wedge that would allow Jewish visitors into Moscow, where they could connect with Jews in the Soviet capital. Isi was deeply hurt by the attacks against him, mainly because he was abroad and could not adequately defend himself. How could anyone who knew him even think that he would betray the cause of Soviet Jewry for profit?”

For many diaspora Jews, Isi Leibler was catapulted into the public eye when his wars began with the World Jewish Congress, of which he had become senior vice-president after settling in Israel with his wife and family in 1999.

At much the same time Leibler — for whom the word “cantankerous” could have been coined — began writing strident columns in the Jerusalem Post, often from a right-wing perspective. Few communities escaped excoriation from Leibler. British Jews were a frequent target, accused of what he believed was the over-arching crime of being “shtadlanim” — “court Jews”, who preferred quiet diplomacy rather than setting problems front and centre on the table and hammering out a solution.

His first war with the WJC erupted in 2003, after its then secular president, Edgar Bronfman, the Seagram’s distillery millionaire, wrote, together with former US Secretary of State Lawrence Eagleburger, to President Bush, asking him to exert more pressure on Israeli premier Ariel Sharon.

Leibler exploded and denounced Bronfman. A series of vitriolic emails were exchanged, with Bronfman calling Leibler “a twit” and “a right-wing dog” (and worse) and saying he felt sorry for Leibler’s “long-suffering wife” Naomi.

It didn’t take long before Leibler began to challenge the working methods inside the World Jewish Congress, saying of Bronfman that “whenever he gets up and says anything, no matter how stupid, the prevailing attitude is, this guy is paying for everything, so for God’s sake, don’t upset him”.

The fact that Leibler was equally rich and equally impervious to criticism does not seem to have fazed him. He went on to charge corrupt practices inside the WJC, specifically targeting Bronfman’s right-hand man, Israel Singer.

Interviewed by the JC in 2006, in the middle of his wars with the WJC, Leibler insisted “they’ll rue the day they started this”. It’s difficult to know, at this distance, whether “victories” such as “proving” that Singer did not have the academic qualifications he had claimed, mattered in the great scheme of things.

But Leibler believes his actions against the WJC and later the Claims Conference, in forcing them to be squeaky clean and transparent, were justified and vindicates him. Now 86, he still fires broadshots against diaspora Jews whom he thinks are not stepping up to his exacting standards. This book, he says, presents his case, with all its warts — yet he still believes he is “a lone voice”.

Lone Voice, The Wars of Isi Leibler, by Suzanne Rutland, is published by Gefen Books.