A strong hand pushed my head under the watery kie’a (clay) that stained the bathtub red. I’d been searching for Rapa Nui for a long time ­– and it seemed that in this strange moment I had finally found it.

Easter Island, its Polynesian people and their language are all called Rapa Nui. They’ve lived on this remote island since at least the 12th Century, when they sculpted the first of its iconic Moai statues, all of which symbolically face inwards. Knowing this, I’d always imagined the Rapa Nui to be a conservative culture, their dramatic isolation creating a society of unshakable traditional values. But when I saw a photo of a Rapa Nui tobogganing down the grass slope of a volcano on a banana-tree trunk, it left me wondering: what does it mean to be an islander today?

I arrived in Hanga Roa, Rapa Nui’s only town, for the two-week festival of Tapati, a contest of dance, drama, cookery, song and sport that takes place at the start of each February. Tapati is organised for the Rapa Nui, by the Rapa Nui, largely in the language of Rapa Nui – reflecting the fiercely independent nature of this culture that for 500 years believed they were the only people left on Earth. Headlining the festival were feats of warlike bravery – perhaps an echo of the island’s rediscovery on Easter Day 1722 and the turbulent history with outsiders that followed.

They believed they were the only people left on Earth.

But at the first contest – the triathlon – I discovered a rather less ferocious item of Rapa Nui identity: the hami (thong). Men wear the hami and little else during festival activities, often adorned with colourful shells. To find each event, I frequently just followed these scantily clad, perfectly tanned bottoms across the length and breadth of the 160sqkm island.

The Haka Pei, or the banana tree-trunk toboggan run, was easy to find. When your nearest neighbours are more than 2,000km away, it's amazing where a strong imagination, a banana tree sledge, a steep grass slope and a razor-thin hami can lead. The Haka Pei is probably the wildest thing you can do with your clothes (barely) on.

With drums beating and crowds roaring, the whole island seemed to be in attendance. I watched the competitors on the summit of the Maunga Pu volcano solemnly join hands.

“Look at Ata,” my host Kau Tepano said, pointing at a young competitor. Thick with body paint, tight with tensed muscles and dressed in only his hami, 18-year-old Ata looked like a warrior. “He is here for his mother,” Tepano explained. “She recently passed away.”

Through chanting, prayer and a bite from a shared chicken leg, competitors began to commune with their ancestors. Despite the competitive atmosphere, “this is actually the most important part of the day,” Tepano said.

As the Rapa Nui lifted their toboggans made of two banana tree-trunks lashed together to the lip of the descent, some of their faces were fixed in ecstasy, others in fear, and a few, like Ata’s shining with pride. The teammates pushed Ata’s toboggan until they could no longer keep up, and then left him to accelerate downhill, lying feet first on the precarious contraption until he became an 80km-per-hour blur of grass and flesh and wood. Although he didn’t win, he arrived at the foot of the volcano safely and leapt from his toboggan in joy at being alive, ­his communion with his recently departed ancestor complete.

Some of their faces were fixed in ecstasy, others in fear.

But Tapati was not all adrenaline and warlike ceremony. Despite the Rapa Nui’s veneration of athletic prowess, those strong men in hamis would sometimes surprise me, participating in a Kakaka competition where they would patiently beat banana bark for hours until it turned into parchment. Or competing alongside the women, using banana leaves to cook curanto (a dish of slow-cooked sweet potato and meat) in an underground oven.

My appreciation of the Rapa Nui’s softer side took an even more unexpected turn at the Crown of Flowers competition. In the shade of a cool marquee, some 100,000 petals lay scattered and 12 young women sat threading 12 rainbows through lattices of shredded banana leaves. The crafting of the crowns was overseen by an elderly matriarch who picked her petals with long, thin, deliberate fingers.

“Is she your grandmother?” I whispered to the girl closest to her. “She is grandma to all of us,” she said, and then, with reverence, “She is ancestral.”

After two hours work, just before the crowns were laid out for the judges to award their points, I was surprised by the sound of a deep male voice asking me: “How do I look?”

I turned and noticed that I had overlooked the muscular arms and shaded upper lip of this crowned competitor in a dress. “Spectacular,” I said with honesty, if a little taken aback. Maybe it was the extreme heat, or the bedazzling flowers but I was surprised, and pleased, to understand that Rapa Nui society had space for Poma Hina to fit in.

The festival is essential for helping the Rapa Nui connect with their past, their present and with themselves, and never was this more apparent than at the climactic Farándula parade, the carnival where both visitors and Rapa Nui take to the streets in full body paint and costume. Floats of dancers, drummers and carnival divas passed down the Atuma Tekena main street with judges scoring every competitor.

I found myself at the parade preparation in my underpants.

And so it was that I found myself at the parade preparation in my underpants (I drew the line at the hami), surrounded by about 500 men and women naked from the waist up, my head being pushed into a bathtub filled with a thick soup of red body paint.

When I came up for air, I realised that this invitation to participate was the most wonderful experience of the festival so far. As if reading my thoughts, the body painter wiped the red water from my forehead, and whispered in my ear: “Thank you for sharing in our culture.”

This was Rapa Nui. A sense of what it felt to belong.

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