This paper examines shifts over time in the relative demand for skilled labor in the United States. Although de-skilling in the conventional sense did occur overall in nineteenth century manufacturing, a more nuanced picture is that occupations “hollowed out”: the share of “middle-skill” jobs – artisans – declined while those of “high-skill” – white collar, non-production workers – and “low-skill” – operatives and laborers increased. De-skilling did not occur in the aggregate economy; rather, the aggregate shares of low skill jobs decreased, middle skill jobs remained steady, and high skill jobs expanded from 1850 to the early twentieth century. The pattern of monotonic skill upgrading continued through much of the twentieth century until the recent “polarization” of labor demand since the late 1980s. New archival evidence on wages suggests that the demand for high skill (white collar) workers grew more rapidly than the supply starting well before the Civil War.