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Religion has been causing conflict for over 2,500 yearsSTRINGER Iraq/Reuters

Religion has been causing conflict for more than 2500 years, according to new research. This contradicts the long-standing belief that religious beliefs acted as the base for developing societies.

The archaeological study analysed evidence from as far back as 700 BC., to AD. 250. This is the time when it is believed states of religion first became prominent in society.

The results showed that despite popular belief, religion held back communities from growing in the early stages of human development. The researchers suggest that religious rituals, for example, funerals or burials, took place in cemeteries with smaller communities – ultimately forging a tight-knit bond with those individuals, and stopped state institutions being created.

"It doesn't matter if we today don't share particular religious beliefs, but when people in the past acted on their beliefs, those actions could have real, material consequences," said Sarah Barber, researcher on the study. "It really behooves us to acknowledge religion when considering political processes."

The study – from the University of Colorado and the University of Central Florida – used evidence from the Valley of Oaxaca and the Lower Río Verde Valley in Mexico. Both of these areas experience religious conflict, but in different ways.

"In both the Valley of Oaxaca and the Lower Río Verde Valley, religion was important in the formation and history of early cities and states, but in vastly different ways," said Arthur Joyce, lead author of the study. "Given the role of religion in social life and politics today, that shouldn't be too surprising."

In the Valley of Oaxaca, the researchers found that some individuals became 'elite', and began mediating between their communities and Gods. This ultimately angered the traditional leaders of the communities, and led to the rising of a regional state with its capital city of Monte Albán – the Zapotec civilisation.

Similarly, the Lower Río Verde Valley saw more than a dozen religious state institutions rise and fall in quick succession. By AD 100, temples had been built in the lower Verde religious state capital, Río Viejo, but just over 100 years later, they were abandoned.