In Europe, women were allowed to inherit property from both their fathers and their husbands. In most cases, whatever the woman brought into a marriage in the form of a dowery was hers, even if her husband divorced her. If a woman was childless or her children were to young to inherit, she would control her husband's property after his death. This was common because of the trend of women in their teens marrying men 10-20 years older.
Some women gained control of their husband's property because they left for the crusades and the wife ran the business in the husband's absence. Some men were gone for years and some never returned.
Women had control of certain areas of commerce of their own volition. Silk spinning was almost exclusively "women's work" Women manufactured purses and ladies hats, too. And in some parts of Europe, such as Paris, they were allowed to run brothels and taverns.
In the Hollister Sourcebook, there is a picture from a French manuscript depicting a woman as an artist painting a woman. The caption states women of the Middle Ages participated in the business world in a way that only men would be allowed to in later times, which included "trade, banking, the direction of business enterprises, textile manufacturing, brewing, tax collecting, money lending, illuminating and copying books,... and a variety of other activities."
Women could even belong to guilds and some taught their knowledge, not only in artisan occupations, but also reading, writing and arithmetic. A woman could be as educated as her male counterpart. Women also were midwives and often served as a sort of doctor giving medical advice and...