The Canadian prairies are a highly productive agricultural zone with a short growing season and a high proportion of land devoted to production of annual grains. Perennial grains and oilseeds are capable of extending the growing season while providing grain, forage, or biomass. Candidate species for perennial grains and oilseeds lack basic agronomic and genetic characterization to support breeding efforts, limiting the ability to develop perennial grain cropping systems. The purpose of this thesis was to characterize the candidate perennial oilseed species Maximilian sunflower (Helianthus maximiliani Schrad.) for the development of a locally adapted perennial oilseed crop for the Canadian prairies. This work consisted of three primary studies examining the phenotypic characteristics of Maximilian sunflower and related perennial Helianthus species, the adaptation of germplasm to its environment of origin, and the development of genomic resources for breeding Maximilian sunflower. Local environmental clines influenced population structure and phenotypic differentiation in Maximilian sunflower, including important adaptive characteristics such as timing of anthesis. Genomic analysis revealed a highly heterozygous genome and low levels of population structure. The first reported genetic map of Maximilian sunflower was developed. Variation in important domestication syndrome traits such as branching architecture and capitulum size were observed in wild sampled and experimental mapping populations. Association and QTL analysis revealed candidate SNPs for multiple agronomic traits and adaptation to local environmental clines to support the neo-domestication of Maximilian sunflower as a perennial oilseed crop. The research contained in this thesis identified variation in key traits in Maximilian sunflower indicating advancement under selection for domestication is possible.