The 22nd Congress of the Indo-Pacific Prehistory Association (IPPA) took place in Chiang Mai, Thailand, from 6 to 12 November last year. What a huge pleasure it was, after the arid COVID years, to meet friends and colleagues once more, and catch up with what has been going on. I even had the company of my son Tom after months of separation. The IPPA has been growing exponentially, and one of the highlights was the number of young archaeologists from Asian countries attending and giving presentations on their fieldwork. There are also great locations for the congress to take place. The last one was in Hué, Vietnam, the old royal capital, where our field trip took us to the palace compound of Vietnamese kings, now restored after becoming the epicentre of the Tet Offensive in 1968. Prior to that, we all met in Siem Reap, and were dropped off at the western gate of Angkor Thom, the city of Jayavarman VII, before roaming round the temple mausolea of Jayavarman and Baphuon, the latter belonging to his predecessor Suryavarman I.

Even without a single Chinese archaeologist in attendance, due to strict travel restrictions, there were so many delegates that we were confronted with six parallel sessions, and hard choices had to be made. For one, however, the choice was made for me. On Tuesday 8 November, there was ‘A special panel in honour of Professor Charles F W Higham ONZM’. Three years ago, my friend Oli Pryce had organised a meeting in the French Alps to celebrate my 80th birthday. It had to be postponed because of asbestos removal. It was then postponed again due to the outbreak of COVID, and finally the session in Chiang Mai took its place. I listened in awe to the range of topics covered. First, my co-director since 1985, Rachanie Thosarat, gave a résumé of where we dug and what we found. Then there were papers from China and Vietnam. Matthew Spriggs gave a most interesting summary of dating under the rubric ‘chronometric hygiene’, certainly a topic that has been central to my research. I cannot mention all contributions, but I must note that Sarah Paris gave a fascinating talk on the use of red ochre in the mortuary traditions at Khok Phanom Di, a paper that was to win her the prize for the best presentation from a graduate student when awards were announced at the farewell dinner.
I had not known anything of the evening party that would follow until I was invited that day. Tom, forewarned, had brought a jacket for me to wear, since I had not brought my own. Properly attired, we took the short walk to the headquarters of the École française d’Extrême-Orient. This is a quite magic complex in old teak, with gardens ringed by huge trees, and the evening was hosted by my friend Christophe Pottier. Greeting me at the entrance was the New Zealand Ambassador Jonathan Kings, who had specially flown up from Bangkok with a large offering of wine. Before long, he was standing on a raised pavilion giving a speech that described my contribution to New Zealand–Thai relations. As he spoke, someone whispered in my ear that I was next. I ascended the stairs and gave thanks to all my friends and colleagues, ending with my gratitude to my wife Polly for keeping the home-fires burning while I was in the field, once for as long as seven months at Khok Phanom Di. Then the evening progressed to a fine buffet, during which I met Sarah Taylor, the Canadian Ambassador to Thailand, who as a student had been with me at Khok Phanom Di in 1985.
Tough choices
Enough of my celebrations. It is hard to choose which sessions stood out for me because there were so many. I began with that organised by Kira Westaway and Renaud Joannes-Boyau on the dispersal of modern humans into Asia. There is a debate as to when this happened, revolving round a long or short chronology. The former is based on fragmentary human remains largely washed into caves in southern China and South-east Asia without any cultural context. Some of these have been said to date the arrival of Anatomically Modern Humans as early as 130,000 years ago, but new dating, often of the fossils themselves, has largely set this model aside. A highlight for me in this session was the new finding from Tham Hua Ngu, the Cobra Cave, in upland Laos. Fabrice Demeter described the great depth of the deposits at this site, and the recovery of a human tooth. Intensive analytical techniques identified this tiny tooth as probably a Denisovan. This recently discovered human species is the focus of intensive research, as its DNA and distribution are mapped.

Myanmar is a newcomer to the study of South-east Asian prehistory. Twenty years ago, I joined a group of colleagues to visit, at the invitation of the Myanmar government, the first Bronze Age site to be discovered there. Located on an extinct volcano near the Chindwin River, Nyaung’gan is a cemetery in which the dead were accompanied by bronze socketed axes. However, local restrictions meant that the graves remained in the ground, thus inhibiting any research on the site. Since then, there has been a flowering of fieldwork under the direction of Oli Pryce and Bérénice Bellina, and we were treated to a series of papers, some by Zoom from Myanmar archaeologists, that brought us up to date. New excavations at Nyaung’gan, at nearby Oakaie, and outside the city walls of the great Pyu centre of Halin, are revolutionising our appreciation of what went on. The vital importance of a Yunnan–Myanmar trade axis has been identified, and who could have anticipated that some of the copper at Oakaie was sourced 1,250km to the east at the Vilabouly mines in Laos? But the session on Myanmar had a sad conclusion: all of this promising fieldwork has ground to a halt thanks to General Min Aung Hlaing and his junta.
Melissa Cadet gave a memorable presentation on Vilabouly itself. This giant deposit of copper ore and gold has been mined by Rio Tinto, an Australian company that engaged Nigel Chang, and then Melissa and colleagues, to excavate ahead of modern ore-extraction. Mining commenced at the very start of the Bronze Age, in about 1000 BC. Some of the shafts descended up to 40m to reach the copper ore. But work there has come to an end, too, as a Chinese company has taken over the permit. However, we have now on record the châine opératoire there, from the actual mining to smelting and the casting of three types of ingot, of socketed axes, and, as time progressed, bronze drums and halberds of Chinese form.
The application of LiDAR at Angkor has clarified a host of issues, not least the layout of the houses, roads, and ponds at Angkor Wat and the city of Angkor Thom. LiDAR has now been applied to many locations beyond Angkor, and I chose papers on two sites. Banteay Chhmar is a temple centre in the far north-west of Cambodia, where a huge irrigation system involving a reservoir and canals has been identified. The same advances have been made at Jayavarman IV’s new capital at Koh Ker. Sdok Kak Thom is a provincial temple complex in Thailand best known for its inscription that describes the ancestry of the lordly author going back more than 200 years. Now we have new insights into its irrigation system, one vital to the well-being of the Angkorian kingdom. Indeed, it was climate change bringing floods interspersed with arid years that led to the abandonment of the site by king and court, and the moving of the capital to the vicinity of modern Phnom Penh in the 15th century.
I must mention what to me, was the absolute highlight of the presentations. Eske Willersev is the Lundbeck Foundation Professor at the University of Copenhagen and Director of the Centre of Excellence in GeoGenetics. In 2019, the Marsden Fund, in its wisdom, declined the best application I ever made for a research grant: to try to extract ancient DNA from prehistoric people I had exhumed at the site of Non Ban Jak. By a lucky coincidence, I was in Cambridge when Eske brought over his team for a week’s retreat. He asked me to give a talk on my site, after which he said, ‘This is super important and we must do it.’ Over the past three years, his post-doctoral colleague Hugh McColl has recovered full genomes from 36 Iron Age individuals, making Non Ban Jak the most densely sampled site for ancient genomes from the region. The dead had been buried in the rooms of their houses. We found, for example, a pair of graves in one room, and another person buried in the room next door, in the same house. How were they related? In his paper, Hugh summarised two of the many fascinating results that are emerging. One covers how the population changed over time, the other described the genetic relations between the Iron Age population of the town. I was so grateful to Eske for realising this, one of my most keenly anticipated endeavours.
Charles Higham is a Professor at Otago University in New Zealand, and an authority on Cambodia’s Angkor civilisation and Ban Non Wat in Thailand.