In this note we examine the nomenclature and extend the descriptions of the subspecies of Francisella tularensis McCoy and Chapin that were proposed by Olsufjev and Meshcheryakova (J. Hyg. Epidemiol. Microbiol. Immunol. 26:291–299, 1982) but have not been validated by publication or listing in the International Journal of Systematic Bacteriology. Biochemical, pathological, ecological, and geographical characteristics are used to define three subspecies within F. tularensis; these are F. tularensis subsp. tularensis (McCoy and Chapin) subsp. nov. (type strain, GIEM Schu), F. tularensis subsp. holarctica Olsufjev and Meshcheryakova 1982, 296 (type strain, GIEM 503), and F. tularensis subsp. mediasiatica (Aikimbaev 1966) Olsufjev and Meshcheryakova 1982, 296 (type strain, GIEM 543). F. tularensis subsp. holarctica includes three biovars, I Erys (erythromycin susceptible), II Eryr (erythromycin resistant), and japonica. The now avirulent type strain of F. tularensis McCoy and Chapin (strain B-38 [= ATCC 6223]) is not totally characteristic of F. tularensis subsp. tularensis, and that is why another type strain is proposed for this subspecies.