Louis Maire (also Lemaire, le Maire) had French parents. He served in the Prussian Army during the Napoleonic wars, perhaps as a surgeon, with J.L.L. Mund* and Carl H. Bergius*. He also trained as a gardener in Berlin. In 1816 he was sent to the Cape with Mund by the Prussian government to collect natural history specimens for the Zoological Museum and Botanical Garden in Berlin. Travelling via England, where they met Sir Joseph Banks*, they arrived at the Cape in October 1816. Dr M.H.C. Lichtenstein*, Director of the Berlin Museum, had given them instructions on how to prepare natural history specimens, with special attention to birds. At the Cape Bergius showed them some interesting collecting localities. They collected around Cape Town for some time and then moved eastwards. From about the middle of 1819 they were in the neighbourhood of George and Knysna, for on 6 January 1820 James Bowie* wrote to Sir Joseph Banks from Knysna stating that they had been in the region for six or seven months and offering the opinion that "the European garden will benetif little or nothing from their labours" (Robinson, 1965/6, p. 91). Maire was then at Plettenberg Bay, while Mund was visiting the Little Karoo. According to Bowie they concentrated more on animal skins than on plants, but had not sent any material to Europe during the previous year. The two collectors probably proceeded as far as Uitenhage.
In March 1820 Dr Lichtenstein complained in a letter that Mund and Maire had not sent him anything of importance yet and that he had not heard from them for two years. In a letter to J.D. Hooker* at Kew Gardens, Dr George Thom* also stated in March 1824 that the two had been waisting their time enjoying themselves in Cape Town. The Prussian Government recalled them, but they ignored the order and their contract was terminated in 1821. However, they sent two large consignments of specimens to Europe. One of these, consisting of two wagon loads of natural history specimens, left the Cape in March 1822. At that time, according to Ludwig Krebs*, Maire was living in Plettenberg Bay.
Both Maire and Mund remained at the Cape. Maire set up practice as a medical practitioner in Graaff-Reinet, where in 1833 Dr Eugene Casalis (father of Dr G.A. Casalis*) met a Dr Lemaire who said that he had been a surgeon in the Prussian army in 1815, and had then been sent to the Cape on a botanical expedition by the King of Prussia. Maire contributed "Remarks on the mineral springs of the Koogha" to the South African Quarterly Journal (1831, Vol. 1(3), pp. 27-30). In 1845 he applied to be allowed to practise as a chemist and druggist in the Cape Colony.
Maire is commemorated in the plant genus Mairea. Herbarium specimens collected by him are in, among others, the Botanischer Garten und Botanischer Museum, Berlin; the Royal Botanical Gardens, Edinburgh; and Kew Gardens.