Montague Stanley Napier (14 April 1870 – 22 January 1931) was an English automobile and aircraft engine manufacturer. His grandfather, David Napier (1785–1873), had moved to London from Scotland and by 1836 had established an engineering company in Lambeth called D. Napier & Son. Montague Napier bought the business from the executors of his father's estate in 1895, and diversified into producing machine tools for the cycle industry.
Following a meeting with businessman and racing driver Selwyn Edge in 1899 Napier diversified into automobile manufacturer, and for a time his company was the leading supplier of luxury cars in the British market. His focus switched from cars to aircraft engines after the outbreak of the First World War in 1914, and he developed the very successful Lion engine.
Napier's failing health forced his move to the south of France in 1915, but he continued to work as a design consultant for his company. He died at his home in Cannes on 22 January 1931, aged 60.
Motor historian Peter King describes Napier as "very secretive by nature"; not much is known about his early life. He was born on 14 April 1870 at 68 York Road, Lambeth, London, the youngest of the four sons of James Murdoch Napier and his wife, Fanny Jemima, née Mackenzie. His father had taken over his own father's interest in the engineering business he had set up there by 1836, making printing machinery for the newspaper industry. The business diversified unto making coin-weighing machines for the Royal Mint, but by the time of James Murdoch Napier's death in 1895 it was in decline. Napier had worked in the family business from an early age, but he was not doing so at the time of his father's death. He bought the business from the executors of his father's estate and diversified into producing machine tools for the cycle industry.
Napier met Selwyn Edge in 1899, for whom he agreed to build a car based on Edge's Panhard et Levassor, which he had bought after it came second in the 1896 Paris–Marseilles race. So impressed was Edge with the result that he contracted to buy six more cars, and set up a showroom in London from which to sell them. The first cars were ready by 1900, and so successful were they that Napier decided to move his company to larger premises in Acton, London. While Napier concentrated on the engineering Edge focused on the marketing and publicity. In 1902 he drove a Napier to victory in that year's Gordon Bennett Cup, the first British victory in an international motor race. Until 1906 Napier cars dominated the British luxury car market, but Napier was unconvinced that there was a sustainable long-term market for such vehicles, unlike Rolls-Royce, his main competitor. Napier therefore set up a new company to develop more popular cars.
Following the outbreak of the First World War in 1914 Napier's interest turned increasingly to aircraft engines. Initially Napier's built engines designed by the Royal Aircraft Factory, but at his own expense Napier subsequently designed his own, the Lion. By 1924 about half of all British aircraft were powered by Napier's engine, and Napier automobile production had ceased.
Napier's health had broken down by 1915, probably as a result of cancer, and he moved to the south of France from where he continued working as a consultant to his company. He was unable to design a satisfactory successor to the Lion, and therefore Napier was overtaken in the aero-engine market by Bristol and Rolls-Royce. Napier died at his home in Cannes, Villa des Cistes, on 22 January 1931, aged 60. The income from his estate of more than £1 million was left to his nurse and reputed mistress, Norah Mary Fryer, for the duration of her life, after which the residue of the estate was to be given to cancer research. In 1903 he had married school governess Alice Caroline Mary, née Paterson, with whom he had two sons and two daughters, but the couple were legally separated in 1922.