In many societies around the world magic was once an essential part of the people's lives. It is fortunate for us now that there has been a renewal of its importance but it is still not essential like it was to traditional societies. There were many names for the magic user. Among them there are witchdoctor, shaman, wise man/woman, and medicine man/woman .
These magic users were revered by the people for their abilities to foretell the weather to ensure a good crop or their knowledge of medicine and healing. They also protected the people in their communities/villages. The people of these traditional societies often believed that an illness or ill fortune was caused by an evil person casting a curse on them. They would go to the village magician for help. The shaman or what ever he/she was called would provide protection and try to root out the source of evil.
Neo-shamanism has become quite popular today but many Native American cultures have had some form of shaman belief for years. However, the traditions of the tribes vary from each other and most of the time they safeguard the knowledge of Shamanism. This is why Neo-shamanism has emerged because traditional beliefs are unavailable or are incomplete.
The Native Americans are not the only society to have shamans though. The practice of Shamanism is quite popular in Norse Heathenry as well. The traditions vary from culture to culture but there are some consistencies.
Usually a shaman is selected by the spirits. He or she can be selected in a number of ways but the most common is after a near-death experience. This kind of experience brings the soon-to-be shaman very close to the spirit world where he or she will receive the abilities to be a shaman. The shaman will be inspired to perform songs and/or dances in his rituals for specific purposes. The shaman also will obtain his tools over time. The tools include a drum and rattle, furs and claws, and a tool that resembles a dream catcher that is used to gather lost souls. Shamanism held an importance of the spirits, ancestors, and nature.
The earliest known evidence of shamanism originates in Siberia, however there is also evidence(cave illustrations) which show that caves all over the world where used for magical/pagan practices. The Native Americans, the Norse, African tribes, Siberians, etc. The list goes on. These people all had important spiritual leaders in their communities.
There were of course other forms of magic and different paths of the many and diverse societies of ancient times. Not all were shamans. The traditional cultures revered nature and the spirits of the Earth. They worked with the divine and with the mundane. They were healers and storytellers.
Sources
* My Brain
* The Learned Arts of Witches and Wizards by Anton and Mina Adams
* http://www.eaglespiritministry.com/teaching/sc/sc1.htm
* http://kaykeys.net/spirit/shamanism/shamanicbasics.html