Female hysteria was actually women's sexual frustration. The history of vibrators is a strange tale that provides insights into both the history of sex toys, and cultural notions about women's sexuality.
Until the 20th century, American and European men believed that women were incapable of sexual desire and pleasure. Women of that era basically concurred. They were socialized to believe that "ladies" had no sex drive, and were merely passive receptacles for men's unbridled lust, which they had to endure to hang on to their husbands and have children. Not surprisingly, these beliefs led to a great deal of sexual frustration on the part of women.
Over the centuries, doctors prescribed various remedies for hysteria (named for the Greek for "uterus"). In the 13th century, physicians advised women to use dildos. In the 16th century, they told married hysterics to encourage the lust of their husbands. Unfortunately, that probably didn't help too many wives, because modern sexuality research clearly shows that most women rarely experience orgasm from intercourse, but need direct clitoral stimulation. For hysteria unrelieved by husbandly lust, and for widows, and single and unhappily married women, doctors advised horseback riding, which, in some cases, provided enough clitoral stimulation to trigger orgasm.