What were traditional views that led people to disapprove of a woman's right to vote?

Women were seen as "the weaker sex."

Women were viewed as being too frail and too emotional to handle thinking about serious topics. Politics and business were considered the domain of men. Women were better off in areas such as literature or music.

It was actually believed at one time that women's brains were not as big as men's. Of course, it was men who said this.