Contrary to the prevailing mythology advanced by some commentators, there is no meaningful comparison between the Kalgoorlie by-election of December 1920 and today’s by-election in the NSW seat of Eden-Monaro.

Sure, the former took place at the time of the Spanish flu pandemic of 1919-20 and the latter is under way during the COVID-19 pandemic a century later. But that’s about it.

The Kalgoorlie by-election of 1920 is the only occasion since Federation in 1901 that a government has won a seat from its opposition in a by-election. That’s a fact. But it is not a precedent since there is no evidence that the pandemic, which was fading by the end of 1920, played a key role in the campaign. Nor did the handling of the medical crisis lead to higher ­approval for the prime minister of the day, William Morris Hughes.

Hughes had a following as a successful war leader — he won elections in 1917, 1919, 1922 and was never defeated in the polls. But a century ago health was overwhelmingly a matter for the states and there was no federal health minister.

What’s historically important about the by-election in Western Australia a century ago is that it took place in a climate of anti-Catholic sectarianism. In the December 1919 federal election the sitting Labor Party candidate, Hugh Mahon, retained his seat with a vote, after preferences, of 52 per cent.

The Labor Party had split in 1916 over conscription for overseas service during World War I. ­Hughes, the prime minister, left Labor with some fellow conscriptionists and formed a National Labor government with the support of the main conservative party. Later National Labor joined with the conservatives to form the Nationalist Party, which was also led by Hughes.

Hughes, born in London to Welsh parents, was a great hater. So was Mahon, who was born in Ireland. The former was a notional Anglican, the latter a believing Catholic. Both men used vitriolic language when it pleased them.

Catholics had enlisted in the Australian Imperial Force in 1914-18 around the same rate, per head of population, as non-­Catholics. However, some Catholics, most notably the archbishop of Melbourne, Daniel Mannix, were prominent anti-conscriptionists in the 1916 or 1917 conscription plebiscites or both. They were not alone. The trade unions were opposed to conscription, as were some rural interests.

Anti-Catholic sectarianism had been part of modern Australia since European settlement in 1788 but attitudes waxed and waned ­according to the political climate. It was at a peak during the final years of World War I and immediately after.

In late 1920, the Anglo-Irish War was under way as some Irish attempted to drive the ruling British out of Ireland. On November 7, during a public meeting in Melbourne, Mahon condemned British rule in Ireland. The most comprehensive account of his speech was published in the Argus newspaper the following day.

In a bitter rant Mahon urged that “the foundations of this bloody and accursed Empire”, the British Empire, should be shaken to the ground. He also welcomed the fact police in Ireland had been shot. It was all too much for ­Hughes who, a couple of days later, successfully moved that he be expelled from the lower house on account of his “seditious and disloyal utterances”. The motion passed on party lines.

After being expelled from parliament, Mahon attempted to win back his seat in the Kalgoorlie by-election of December 18, 1920. He lost to the Nationalist George Foley (a Protestant) winning 48.6 per cent of the vote — a swing against Labor of 3.5 per cent. Mahon did not contest Kalgoorlie in the December 1922 general election at which Labor’s (Protestant) candidate Albert Green won back the seat with a vote of over 57 per cent.

The evidence suggests that sectarianism played a part in the Kalgoorlie by-election, which took place at a time when individuals close to the Hughes government were working to get the Irish-born Mannix exiled from Australia. However, anti-Catholic sectarianism had waned by the end of 1922. The Anglo-Irish Treaty had been negotiated and 26 of 32 Irish provinces had won relative autonomy.

Compared with Kalgoorlie a century ago, Eden-Monaro is just a routine by-election. In which case, Labor should start favourite to retain the seat vacated by popular member Mike Kelly. The bushfires of early in the year and the subsequent pandemic have adversely affected Eden-Monaro. But unlike Mahon in 1920, the major candidates Kristy McBain (Labor) and Fiona Kotvojs ­(Liberal) have no history as parliamentarians and carry no political baggage.

The Kalgoorlie by-election in 1920 became a historical incident but no more than that. Within a few years, the politics of the seat returned to normal. Whatever the outcome in Eden-Monaro today, the by-election is unlikely to have a long-term impact on Australian politics.

Certainly Scott Morrison would benefit from gaining an extra seat in the House of Representatives over the next two years if the Coalition prevails over Labor.

And Anthony Albanese would be disappointed if Labor loses — but would be likely to retain his leadership position since it is difficult to assess an opposition’s performance at a time of pandemic.

The problem is that no one has any idea what the political and economic situation will look like at the next election scheduled for mid-2022. Right now, Morrison’s potential problem comes from the states — not from Albanese. If a number of states continue to close their borders this will slow recovery out of a deep recession. In such an eventuality, the federal government might suffer at the next election due to the protectionist attitudes of some states leading to a slower recovery than would otherwise be the case.

Viewed in this light, the Eden-Monaro by-election is likely to be less important than currently appears to be the case. In which case, like Kalgoorlie a century ago, the result could be less significant than it may appear after the votes are counted.