In the Middle Ages (19th Century)
Also now.
Yes.
Superstition, resulting from spread of disease.
The powerless are prone to believe in the supernatural. If people around you believe something, you are more likely to believe it.
Some people may believe it is. It is not if the person saying does not believe it.
Although many people do have some doubts about witchcraft. John Proctor and Rebecca Nurse are the ones who openly deny it.
Politics may be or may not be associated with corruption, violence and ignorance depending on the country, people and constitution. But that has nothing to do with Witchcraft, and neither witchcraft is necessarily a dark art.
Because it existed and still does, though it is not evil as it was commonly believed to be.
People still believe in witchcraft and witches. This has never gone away, but centuries ago people who had red hair were often seen as witches and people who were not part of a community but considered outsiders or odd were seen as witches. Witchcraft was often used to explain events in a community.
Its easier to explain unfortunate events, people seek an explanation and that's the easiest approach. Its a form of social control, like religion and laws.
That depends on the scientist. Like all people, scientists are free to make up their own minds about what they do and do not believe. I know several people who have careers in the sciences who are also practicing pagans. Some of them practice forms of what could be called "magic" or "witchcraft".
Yes they did. They so believed in witchcraft that they persecuted and killed anyone they felt was practicing witchcraft. See the link below.
Yes witchcraft does exist. It is one of many spiritual paths available. Finding someone to teach you should be done locally. You need to be able to sit down with your mentor, talk to him or her and watch what they do. Much of what we do is as much in the gestures, movements and physicality as it is in the words, herbs and spells.