Spencer Fullerton Baird created the genus "Ergaticus" in 1865, using it to separate several species from what he felt was the closely related genus "Cardellina". Prior to the creation and widespread acceptance of this genus, the red warbler and pink-headed warbler were placed in various other warbler genera, including "Setophaga" (with the American redstart), "Cardellina" (with the red-faced warbler), and "Basileuterus" (a widespread genus of tropical warblers) — as well as the Old World warbler genus "Sylvia" and the Old World tit genus "Parus". Recent DNA analysis shows that "Ergaticus" falls comfortably within the New World warbler clade, along with 18 other genera. It is closest to the genus "Cardellina", with which it shares a common ancestor, and slightly more distantly related to the genus "Wilsonia".