Swedish botanist at the University of Uppsala who travelled widely, collecting plants in Africa and South America several times. Born in Uppsala, Fries came from a line of distinguished botanists; his father was the lichenologist Thore Magnus Fries (1832-1913) and his grandfather the mycologist Elias Magnus Fries (1794-1878). Fries' brother (Thore C.E. Fries, 1886-1931), son (Magnus Fries, 1917-1987) and nephew (Nils Fries, 1912-1994) were also botanists.

Aged 25 Fries joined the Swedish expedition to the Chaco desert and mountain ranges in Argentina and Bolivia, led by Baron Erland Nordenskiöld. He returned in 1902 with a substantial collection of phanerogams, fungi and algae, which he studied at Uppsala, where he gained his doctor's degree in 1905. His thesis was entitled Zur Kenntnis der Alpinen Flora im nördlichen Argentinien (The Alpine Flora of Northern Argentina). While teaching at Uppsala, he made his first trip to Africa, accompanying Eric Conde Von Rosen. Setting off in 1911 they traversed nearly the entire continent over the course of the next year, building up a substantial collection of plants from the central region. Fries returned in 1921-1922, making collections in East Africa. He also collected widely in his home country and twice carried out fieldwork in Spain (1906 and 1920).

Having taught at Uppsala for some time Fries was appointed Professor Bergianus at the Bergius Foundation in Stockholm in 1915, where he remained (also as head of its garden, Bergianska trädgården) until 1944. Fries published numerous works on the flora of Africa and the regions he had visited in South America and was an expert on the Annonaceae family and amaranths.

Sources:
C.E. Chardon, 1947, "La contribución del doctor Robert E. Fries a los estudios botánicos del Nuevo Mundo", Darwiniana, 7(4): 497-503
O. Hedberg, 1966, "Robert Elias Fries, 1876-1966", AETFAT Bulletin, 17: 12-13.