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Boloria improba is a Holarctic nymphalid butterfly adapted to high latitude/montane habitats (arctic tundra and moist alpine meadows). In the New World, it is found in North-Eastern Alaska north-east through the Northwest Territories and Nunavut to Baffin Island, south to the Yukon Territories and northern British Columbia. There are also isolated relict populations in the central Canadian Rockies, southwest Wyoming, and southwest Colorado (Britten et al. 1991, 1992, Ferris 1984, 1986). In the old world, Boloria improba inhabits Northern Fennoscandia and the Chukotka Peninsula in North-East Siberia (Henriksen and Kreutzer 1982, Tuzov 2000, Välimäki et al. 2011, van Swaay et al. 2012).
Several subspecies of Boloria improba are recognized. Some authors (Britten et al. 1992, 1994, Ferris 1984, Gall 1984, Gall and Sperling 1980) consider the Colorado populations of Boloria improba to be a distinct species, Boloria acrocnema, while others (Pelham 2008, Scott 1986, Simonsen et al. 2010) treat it as a subspecies, Boloria improba acrocnema. Simonsen et al. (2010) suggest that the improba/acrocnema complex originated in the Nearctic and then dispersed to the Eastern and Central Palaearctic via the third Beringian land bridge (1.5 Mya–10 kya), which was dominated by barren tundra vegetation and thus provided a corridor for tundra-adapted species.