In the history of the American penitentiary, women are, for the most part, invisible. The history of women's prisons and theories on female criminality were not taken into account in the debate. In comparison, there is a large amount of scholarship and literature on men's prisons and prisoners from the same era. This article is an attempt to fill this gap. Featuring Women, Prison & Crime, Women in Prison and Their Sister's Keepers by Jocelyn Byrne, Cyndi Banks and Estelle Freedman, respectively, this article attempts to describe the history of women's prisons and the main theories about women prisoners from 1840 to 1930. By analyzing these two concepts in conjunction with the status of women in society during these particular eras, a trend emerges. Theories about female criminals and the approaches implemented to control them are a direct reflection of society's belief that a woman's place is in the domestic sphere. Thus, from 1815 to 1930, society only considered women as criminals when they left this sphere and all reform efforts were aimed at their return. Creation: 1815-1830Before the prison, there was the scaffold. This public form of corporal punishment was challenged during the Age of Enlightenment in the American colonies. The Enlightenment came with new ideas about what constituted humane treatment. To further align with these ideas, thinkers like Benjamin Rush created the penitentiary to replace the scaffold. Instead of strict punishment, the penitentiary would propose reform. This reform took place according to two distinct models: Philadelphia and Auburn. In both models, prisoners were subject to discipline, work and silence. The only difference is that in the Pennsylvania model, the inmates ...... middle of paper ...... and these theories challenged in 1830, new theories emerged and with them new forms of punishment. One theory insisted that some women were born criminals and therefore could not be reformed. These women were tough masculine women, who committed harsh masculine crimes and were sent to prisons. The other insists that some women simply fell into a life of crime, innocent victims of circumstance, and that with the right help they could become real women again. These women committed victimless crimes and were sent to reformatories. One thing all of these theories have in common is either equating crime with women leaving the home or equating reform with women returning to the home. As a result, the early days of the women's penitentiary allowed society to silence or domesticate women it believed to be against the norm..