Anemone hortensis L. was typified on a specimen with red flowers and obovate tepals cultivated in the Netherlands, originally introduced from the eastern Mediterranean. This red-flowered variant of the species has been in cultivation in northern Europe since the 16th century and is now widely naturalised in northwest Italy and southeast and southwest France. Anemone fulgens (DC.) Rchb., also with red flowers, is shown to be a synonym of A. hortensis. Anemone pavonina Lam. is revealed to have been based on a teratological red-flowered specimen of A. hortensis with multiple tepals and is recognised here as A. hortensis var. pavonina (Lam.) Gren. and Godr. Plants across the range of the species with lanceolate, frequently lilac or purple tepals, which are often incorrectly attributed to A. pavonina, are shown to be A. hortensis var. stellata Gren. and Godr. Plants endemic to Crete and its adjacent islands, with elliptic white or pale pinkish flowers, are recognised as A. hortensis var. heldreichii (Boiss.) Halácsy. A total of 16 lectotypes and one neotype are designated, and a key to the varieties within A. hortensis is provided along with synonymic conspectuses. The new combination A. hortensis f. regina (Risso) J. Compton is made to identify plants with red or purple flowers having a zone of yellow or white at the base of each tepal, collectively forming a pale central circle within the flower.