De Maistre was educated, together with his brothers and sisters, by tutors and governesses at the family home near Sutton Forest.
He studied painting at the Royal Art Society of New South Wales under Antonio Dattilo-Rubbo who encouraged interest in Post-Impressionism, alongside fellow students Norah Simpson, Grace Cossington Smith and Roland Wakelin.
It appears to be indicative of the great desire of the armed forces to procure men for the World War I effort that they would have considered accepting De Maistre once, let alone three times in short succession – and indicative of his great desire to serve in the war effort that he continually rejoined even after he had found himself too weak to cope with the workload.
In November 1916, as Roi de Mestre, he first exhibited, showing Impressionist paintings concerned with the effects of light.
[4] The only existing example of this experiment is Rhythmic composition in yellow green minor (1919),[5] which visualises music slowly unravel through the flow of colours.
Influenced by earlier exponents of "colour-music" theory in Europe and America, this exhibition has since been identified as the earliest experiment in pure abstractionism in Australia.
De Maistre was also interested in interior decoration and the manner in which the colours within a room could impact upon the human psyche.
Discs and scales to help home-owners integrate colour music into their own homes were made available for purchase.
His paintings of 1921–22 are experiments in impersonal, unemotional tonalism, and from the 1930s he turned to a more recognisably figurative style of work generally influenced by Cubism.
He spent three years abroad, studying in London, and in France in Paris and Saint-Jean-de-Luz, where he created Sea piece, St Jean de Luz (1925),[8] a landscape painting featured a mild semblance of his earlier practice with colour and abstraction.
In 1924, while abroad, he patented the "De Maistre Colour Harmonising Chart", which was produced and marketed by Grace Bros, a Sydney department store.
On returning to Sydney, he held one-man shows (1926 & 1928); contributed to annual exhibitions; conducted classes in modern art to private pupils from his studio in Burdekin House, Macquarie Street, Sydney; and organised in his house an exhibition of modern interior design (1929).
The American architect Walter Burley Griffin and de Maistre created the interior decoration for the cafe opened by Pakie Macdougall in Sydney in 1929.
They also both appreciated the benefits of social standing and connections; and Christian symbolism and biblical themes are common in both artists' work.
Patrick White was an art collector who had, as a young man in London before World War II, been deeply impressed by his friends De Maistre and Bacon.
By the mid-1960s he had also become interested in encouraging dozens of young and less established artists, such as James Clifford, Erica McGilchrist, and Lawrence Daws.
In 1940 De Maistre started work for the French Section, Joint War Organization of the British Red Cross Society and the Order of St John, London.
His work was bought for the Tate Gallery and other art museums, and was frequently discussed in the writings of Sir John Rothenstein.
Besides religion his late painting often dwelt on interior intimacies of his studio home and its "artfully cluttered bric-à-brac".