“Scarlet Experiments” frames Dickinson’s poetic practice and later reputation within the context of elite nineteenth-century reviewing and the norms that evaluators established; it focuses on such publications as the North American Review and on judgments concerning her regional contemporaries. Critics’ agitation suggests they felt that potentially unruly poets might defy their normative pronouncements, and that such disruptive writers required explicit chastisement and remediation. Dickinson clearly represents extreme intractability. How does her “New English” speak to the reviewers, particularly to their criterion of originality? How might we understand Dickinson’s perspective and practice differently when we contemplate these evaluations? Examining critics’ views on New England poets and poetry during three moments—1848, the early 1860s, and the decade following her death—illuminates how aesthetic standards may have informed Dickinson’s early development, her most intensely productive period, and her posthumous reputation, especially in relation to how gender informed (and deformed) critics’ responses to female poets, of whom they typically demanded greater conventionality. Reading reviews, Dickinson might have feared significant critical chastisement for her aesthetic experiments and for exploring troubling psychological states, yet she might also have seen reason to feel encouraged. I show how the transforming critical climate finally ensured the poet’s audibility and even popularity; responses to her work illuminate particularly the 1890s period of interpretive innovation. Dickinson’s appearance was perfectly timed to provoke controversy, and her work upended both poetry and criticism, ultimately helping transform the standards for what counted as original American poetry.