Around the time of the arrival of sweet potato some 400 years ago, we estimate that the population of Enga was approximately 20-30,000. MAP 2 gives the location of the Enga tribes that claim to have been resident in Enga Province at that time. MAP 3 gives the location of tribes around the time of first contact with Europeans.

In the fertile valleys of eastern Enga, subsistence farmers grew taro, kotena, yams, bananas, sugarcane and other crops on the lower terraces. Kotena, a large tuber that was tougher than taro, was used as a famine food. Mid-valley slopes were kept for pig forage and the high forest for hunting and gathering. There is an amusing story of a man who had just put his kotena in the ashes when some enemy arrived. He fought off the enemy single handed until his kotena was cooked, so hungry he was: Kotena yangatala yandate nyia.

In central Enga, people cultivated mixed gardens, hunted and gathered wild foods as described in the Malipini origin story:

For western Enga, historical traditions tell a different story. In the high country of western Enga 2100-2200 meters above sea level lived mobile groups who were largely dependent on hunting and gathering. These ‘hunters’ were said to have great physical strength and ritual powers and attained high status. Shifting horticulturalists, who lived from taro, other garden foods, and hunting, inhabited the narrow valleys below. Historical traditions and myth from western Enga depict culturally recognized distinctions between ‘hunters’ and ‘horticulturalists.’ These groups intermarried and exchanged wealth, but also had relationships filled with tension and misunderstanding. Gardening was insecure in the Lagaip and shifting horticulturalists traded with groups to the north for sago and with hunter-gatherers in the high-country meat and forest products.

From the very beginning, Enga appears to have been an open society of travelers, traders and experimenters. Oral traditions describe a sense of loneliness in a sparse population. People traveled extensively seeking trade, spouses, attending rituals, harvesting pandanus in the high forest, or seeking refuge after wars or severe frost. The plots of early oral traditions center around hunting, the trade of salt, axes, tree oil, shells and plumes. A few pigs were kept but not given great importance. Wars were fought to break up communities that had become too large to cooperate or to displace troublesome neighbors. Once they established separate communities, warring clans often resumed intermarriage and exchange. In eastern Enga there was a well-developed trade alliance to import axe stone from quarries in Western Highlands in exchange for salt from the Yandap, amongst many other trade goods. This trade began more than 1000 years ago and was controlled by strong leaders.

Migrations occurred all over Enga in response to potential offered by sweet potato and conflicts generated by population movements (MAP 4). Enga clans settled areas like Kompiam, Maramuni and Porgera for the first time. In western Enga population shifts occurred as groups who had lived largely by hunting and gathering moved down into the Lagaip to take advantage of the easier life possible with the new crop.

The population was sparse at the time so maternal kin and in-laws living in lower valleys sought more clan members to help them with clearing gardens, defending the clan, providing marriage partners and holding festivities. Often relations did not work out as planned and conflicts broke out over work, hunting, gardens, marriage, insult, theft and misunderstanding. Some conflicts escalated into wars that led to migrations to the north, to the west and to the south.

Distressed by frequent warfare, people sought new ways to discipline young men as well as to build tribal unity and cooperation. It is around this time that Sangai ceremonies started in central Enga and spread. The Sangai disciplined young men, kept them under the control of older men and created strong bonds between clan brothers.

Around the same time, Kepele ceremonies for the ancestors were elaborated into five-day celebrations. Tribal members, who had been dispersed by migration, came together bringing food and materials from their areas. During the Kepele, boys were initiated, clans of a tribe unified and communication with the ancestors restored. Relatives from many surrounding tribes came for the celebrations where marriages were arranged and trade goods exchanged. Kepele ceremonies of different tribes were linked with ritual experts from some tribes and many celebrants participating in Kepele rituals of other tribes. The network was described as a snake with its head in Kandep and tail in Porgera though the Kepele was also adopted and modified in central Enga where it was called Aeatee (MAP 5)

In central Enga there are no traditions describing the arrival of sweet potato, though there are some stories of experimentation with the new crop. In the high country of Sirunki and Yandap, where sweet potato allowed for more settled communities, historical traditions suggest that larger cooperative groups were being formed. Around the sixth generation, coordinated groups in the upper Lai and Sirunki launched large-scale attacks to acquire land in the fertile Ambum valley. Ambum residents were forced into the Kompiam area where they formed communities and prospered. These wars had positive outcomes, for example, creating larger cooperative groups and stronger leadership. They also had negative ones: death, destruction and disruption of former networks of marriage, exchange and trade.

In response, the Great Ceremonial Wars, yanda andake, were developed in central Enga out of efforts to maintain some of the positive aspects of the wars and yet to avoid the negative ones. These Great Wars were fought between entire tribes or pairs of tribes in central Enga at 8–12-year intervals. The first ones began in the early 1800s, and the last one was fought around 1940. Allies clans or tribes hosted the ‘owners of the fight’ by providing them with housing, food, water, allies and a battlefield. After opening ceremonies, hundreds of warriors in full ceremonial dress exchanged volleys of arrows while spectators gathered from far and wide to watch. Women danced and sang along the sidelines. Men fought by day and courted women from host and allied clans by night.

These ‘battles without anger’ went on for weeks or months with pauses for participants to go home, tend gardens and rest. Deaths were not avenged and no land was won or lost. When a formal end to battle was called there were huge feasts and thousands of pigs changed hands. The exchanges that followed the battles created marriage ties, partnerships of trade and exchange, and other alliances between clans of the Lagaip, Lai, the Ambum and Sau valleys. MAP 6.

Sweet potato slipped into the garden regime of eastern Enga without note in oral traditions. This may be because crops such as taro, yams and bananas grew well in the fertile soils and were preferred foods. However, sweet potato was adopted quickly as fodder for pigs. Sweet potato did make a difference in the lives of neighbors in Mendi and Tambul who lived at higher altitudes and sought an easier life by migrating down into the fertile valleys of eastern Enga. As in central Enga, these migrations led to conflicts that expelled groups north into the Kompiam area. That is why the northwestern part of Kompiam today is settled by Mai tribes from central Enga and the southeastern part by Layapo from the Lai and Saka valleys.

Migrations in the east also threatened the established axe stone/salt trade. In response, clans involved in the trade developed new economic strategies. Leaders called on distant partners down trade routes to send pigs to supply them with a large amount of wealth in one place at one time to carry out complex political strategies. Pigs and other wealth were paid back at a later date creating the early Yae Tee cycle. Although the Yae Tee began on a small scale, other clans saw the advantages of the economic strategy and joined. Soon there were routes from Tambul, to the Saka, down the lower Lai and through Itokone to Lenge and on to Tetemanda (MAP 7).

From this point on Enga history becomes very complex. By the fifth-generation great leaders, kamongo, from the east became aware of the large amounts of wealth flowing in the Great Ceremonial War exchanges. They timed their Yae Tee cycles so that they would harvest wealth coming out of these exchanges and move it eastward. When it came time for Great War exchanges, leaders in the west would draw wealth from their partners in the east for their exchanges. In this way the systems became closely linked. Coordination of the two large exchange systems was not easy. Leaders of central Enga realized rituals like the Sangai and Kepele made it possible to gather many people in a spirit of cooperation. They imported versions of the Kepele into central Enga from the Lagaip, altered the festivities to suit their needs and renamed it Aeatee. Leaders from along Yae Tee routes were invited the festivities after which plans were made to coordinate the Yae Tee and Great Wars.

Once linked to the Yae Tee, the Great Wars grew rapidly and became complex to organize. Leaders realized that it was much more efficient to maintain ties of trade and exchange through the Yae Tee. One by one the Great Wars were discontinued and their routes replaced by the Yae Tee. The last Great Ceremonial War was fought around 1940. By the early 1950s, the Yae Tee involved most clans of eastern and central Enga, some 275 clans and up to 40,000 participants. It was one of the largest exchange systems known in the world in a society that had no formal state. Had Australian patrols not entered the Enga in 1938-9 to bring about a completely different direction of change, what might have happened next?

This brief overview of Enga history indicates that the people of Enga have long been faced with the challenges of change as they are today. Challenges were particularly serious after the arrival of the sweet potato some 400 years ago when people redistributed themselves over the landscape. Levels of conflict and warfare were high just like they were after the recent adoption of guns into tribal fighting. Enga took action to put order to chaos through devising rituals to discipline young men and promote cooperation within clans and tribes. Elaborate systems of tee exchanges were developed to reduce conflict in the interest of economic cooperation. And so, Enga society overcame serious turmoil to launch into times of growth and prosperity.