A classic joke among pagans is that if you ask four pagans to define paganism, your will usually receive five answers.  Some use the broad definition that Paganism is the practice of religion outside the Abrahamic monotheistic religions encompassing Judaism, Christianity, and Islam.  Another definition supported by the On-line Etymology Dictionary is that Pagans were those individuals that adhered to the old gods after the Christianization of Roman towns and cities.  “Paganus” was Roman military jargon for “civilian, incompetent soldier” and rising Christians used this imagery to refer to those who were not “soldiers of Christ.”  Another definition supported by Random House dictionary was that it was derived from the Latin word “pagus” or village and thus referred to a country-dweller -- probably similar to calling someone a “hick” or “red-neck.”  The term therefore would describe someone that continued to practice the local rural customs rather than the religions being observed in the cities.  The definition that makes the most sense to me is that Pagan is an umbrella term for groups that practice nature-based religious practices.   This can include many modern religions to include Shamanism, Wicca, Asatru, Church of All Worlds, and Druidry.      

Early in mankind’s history, they began to discover relations among various events and natural objects.  Women discovered their bodies were in tune with the lunar phases and that they were the givers of life.  Small figurines of pregnant women made of bone, bone, and clay were found that seem to signify that reverence was given to women for their ability to give life. Since women had the important role of birthing and nurturing the children, men usually became the hunters.  They would learn to wear the animal skins and other parts to camouflage themselves.  The hunters learned the language of the animals and how they were affected by the seasons of the sun.   Man began exploring and discovering the mysteries of life, death and rebirth.  When mankind starting turning to agriculture for food about 8000 BCE, they discovered the relationship of the solar cycle to the growing seasons. 

They eventually began to form a belief that objects and other natural phenomena, such as rivers, rocks and wind, were alive and that they had feelings and intentions.   Eventually, some began to believe that these objects and other natural phenomena had a soul or spirit apart from matter.  This idea is called Animism.  It was morally imperative to treat these agents with respect and humans were considered a part of nature, rather than superior to, or separate from it. In such societies, ritual is considered essential for survival, as it wins the favor of the spirits of one's source of food, shelter, and fertility and wards off malevolent spirits. In more elaborate animistic religions, such as Shinto, there is a greater sense of a special character to humans that sets them apart from the general run of animals and objects, while retaining the necessity of ritual to ensure good luck, favorable harvests, and so on. 

Some of these belief systems evolved to include Panentheism which asserted that God exists and interpenetrates every part of nature and Pantheism which stated that God is nature.  Concepts of each of these exist in most of the world’s religions today.  Some pagans began to believe in Monotheism that asserted that there is only one God or Polytheism which believed in many Gods.   Early examples of each of these existed in Egypt which in general was polytheistic but had once practiced monotheism during the reign of the pharaoh Achnaton during the 18th Dynasty. 

Certain people soon became recognized within the communities that seemed to be able to understand these natural relationships and/or communicate with these spirits better than others.   Some of them might also have been viewed as having special skills in manipulating and controlling the course of nature by preternatural means, i.e. magic.  These people became the highly respected “wise men and women” of the community.

To commemorate or recognize this interconnectedness various yearly events were celebrated.  To appease the spirits and/or Gods, religious rituals and practices were created.  As the cycle of the wheel of the year continued to turn, these traditions soon became part of the culture and an integral part of their lives.   
As cities grew larger, their inhabitants began to feel less connected to nature than the earlier generations.  They began looking at the world in a different way than those still living and working in the country.  Their religious practices also became different.   Organized religion emerged as a means of providing social and economic stability to large populations.  During the growth of the city-states, various religious beliefs began to be shared and mixed between the cultures.  This generally impacted the residents in the cities more than those in the country as the country-dweller was ignored and allowed to follow the religious practices of their ancestors. 

In Europe, the Roman Empire tolerated all religions within its far-flung borders, so long as Rome's official deities received due lip-service, and the deified emperors were properly honored. This policy of religious freedom was abandoned by the Roman church which began to insist that all non-Christian faiths be destroyed.  The third Council of Constantinople decreed in the 7th century that the people must stop kindling bonfires and leaping over them on nights of the new moon. St. Eligius wrote: "Let no Christian place lights at the temples, or the stones, or at fountains, or at trees, or enclosures, or at places where three ways meet...Let no one presume to make lustrations, or to enchant herb, or to make flocks pass through a hollow tree or an aperture in the earth; for by doing so he seems to consecrate them to the devil."   Pagan deities, holy places, customs and holidays began to be assimilated because it was noted that the people wouldn't accept Christianity unless it could be considered an extension of paganism.  Pope Gregory the Great directed that Christian relics be placed in the inner shrines of pagan temples, and the people converted gradually to the idea that there deity was a saint instead of an un-Christian spirit. Pagan feast days were to be Christianized. 

During the Renaissance, although Europe remained Christian, the Pagan gods and goddesses of Ancient Greece jostled with the patron saints of Christianity on public monuments.  Classical philosophy began to change the way people thought about ethics and morality. The Catholic Church was being challenged by the Protestant reformation.  This religious conflict created an environment of religious hysteria (disguised as spiritual cleansing) which led to some individuals being described as 'witches'.  Generally, these people were merely victims of local feuds and quarrels. A few of them were pagans and/or practitioners of herbal medicine but most were ordinary, conventional citizens.  Thousands were executed for their beliefs.
Though Paganism was not stamped out, society did become more detached nature during the subsequent Industrial Revolution and the rise of scientism.  In recently history though, Paganism found an ally in the ecological and feminist movements of the 1960s. Pagan philosophies appealed to many eco-activists, who also saw Nature as sacred.  Nationalist movements spread and traditional festivals and tales were reclaimed.  Native American  and the Afro-American traditions of Santeria, Candomble and Vodoun were rediscovered. European traditions reconstructed local holy sites and resurrected traditional ceremonies.

Bibliography

Ask.com. (n.d.). Pagan. Retrieved 01 24, 2009, from http://dictionary.reference.com/browse/pagan
Bay Area Pagan Assemblies (BAPA). (n.d.). What is Paganism. Retrieved 01 24, 2009, from Sacred Texts: http://www.sacred-texts.com/bos/bos627.htm
BBC. (n.d.). Paganism. Retrieved 01 24, 2009, from http://www.bbc.co.uk/religion/religions/paganism/history/modern_1.shtml
CoyoteSkyWoman. (n.d.). A Brief History of Paganism in America. Retrieved 01 24, 2009, from WitchVox: http://www.witchvox.com/va/dt_va.html?a=usnh&c=words&id=10645
everthing2.com. (n.d.). History of Paganism. Retrieved 01 24, 2009, from http://everything2.com/e2node/History%2520of%2520Paganism
New Advent. (n.d.). Paganism. Retrieved 01 24, 2009, from http://www.newadvent.org/cathen/11388a.htm
Pagan Pride Project. (n.d.). Paganism. Retrieved 01 24, 2009, from http://www.paganpride.org/resources/pen-paganism.html
Reichert-Weygold, G. (n.d.). Pagan History. Retrieved 01 24, 2009, from The Pagan Library: http://www.paganlibrary.com/editorials/paganHistory.php
Tala, G. (n.d.). The History of Paganism. Retrieved 01 24, 2009, from Tala: http://community-2.webtv.net/tala--/THEHISTORYOFWICCA/
Wikipedia. (n.d.). Paganism. Retrieved 01 24, 2009, from http://en.wikipedia.org/wiki/Paganism
Wikipedia. (n.d.). Panentheism. Retrieved 01 24, 2009, from http://en.wikipedia.org/wiki/Panentheism
Wikipedia. (n.d.). Prehistoric religion. Retrieved 01 24, 2009, from http://en.wikipedia.org/wiki/Prehistoric_religion