In the 18th century, the Founding Fathers were considered radical for wanting an educated populace. A nation of educated citizens requires teachers as a fundamental component of the idea of democracy — though in their time, only white, land-owning men could participate.
The Common School Movement
Horace Mann, an American educational reformer, advocated for the Common School Movement, an effort to provide free education to all students regardless of class. Additionally, several normal schools, which are known today as colleges of education, were founded to train teachers.
Horace Mann believed in expanding education to a larger group of people, so he needed a workforce that would work at a price affordable for taxpayers. Unfortunately, women were more affordable, which has contributed to the feminization of the profession.
Other contemporaries, like Catharine Beecher, believed women were “more nurturing,” and therefore, more of a natural teacher.
Prior to this, teaching had traditionally been more male-oriented. All of this contributes to the predominantly female workforce in the profession we know today.