Research puts Tongan development back more than 500 years

A re-evaluation of archaeological sites in Tonga has revealed fascinating detail about city-like structures built on the main island, placing population growth and urbanisation hundreds of years earlier than previously thought.

Results from a survey conducted in 2011 for a Pacific-wide tsunami modelling project, triggered a rethink of built environments in Pacific states.

The study used aerial laser scanning to map the distribution of mounds and fortifications on the landscape of the main island, Tongatapu.

“Urbanisation in the Pacific was an indigenous innovation that developed before Western influence,” says the Australian National University’s Phillip Parton, lead author of a paper outlining the research.

“Earth structures were being constructed in Tongatapu around 300 CE. [That’s] 700 years earlier than previously thought,” Parton says.

The mounds were used as burial sites and household foundations, and for sporting activities: “The final category of built environment features are large mounds called sia heu lupe that were constructed for the sport of pigeon snaring and are characterised by their large size and a central depression.”

Tongan people came from Taiwan.

“As settlements grew, they had to come up with new ways of supporting that growing population,” the authors of the paper write. “This kind of set-up – what we call low density urbanisation – sets in motion huge social and economic change. People are interacting more and doing different kinds of work.”

The researchers calculate the population at Mu‘a, now known as Lapaha, the largest settlement on Tongatapu, was, at that time, home to an estimated 6,700 to 7,600 people living on an area of about 1170ha.

“The settlement density at Mu‘a was 6.16 people per hectare, and the density of settlements larger than 100 hectares varied between 3.80 and 6.47.”

The earliest European accounts all document rectilinear living compounds surrounded by tall fences that prevented unwanted access and reduced visibility from the street.

“While Tongan residences were open sided for comfort, their elevated position on top of durable earth mounds broke street level site lines to further manage settlement stresses and improve amenity during rain and breezes,” says Parton. “The well-developed road hierarchy that crossed Tongatapu provided routes for the movement of goods that minimised interaction stresses on minor roads.

“Many of the architectural features associated with urban institutions are found in the central area of the Mu‘a core…documented traditions identify the location of large open spaces, connective infrastructure, and the residences of political elite and their monumental burials.

“Fortifcations and gates separated land uses and social classes, and a wharf and harbour infrastructure connected the settlement to the Polynesian world. The missionary, the Reverend Walter Lawry, described the settlement at Mu‘a in 1822 as the ‘Metropolis of Tonga.’

“Locations in the Pacific with dense built remains similar to Tonga, and where the fundamental processes behind settlement growth can also be examined with lidar data, include the built environments of Sāmoa, and the centre of Nan Madol in Pohnpei, [Micronesia].”