Around his shoulders, Shimray wears the shawl of his tribe, the Tangkhul, but he is determined that his identity will not be defined by the ridges and rivers his forefathers knew as their borders.

"Tribalism is the biggest problem for the Naga," he says of the nation of four million people, divided over five jurisdictions and two countries. "It is much better now - there is no fighting any more. In the old days, we would meet someone from another tribe and just cut his head off. But still, we are too much divided. We are worried only about our tribe. When we are in Nagaland we are always asking each other, 'Which tribe are you?' We are only Naga when we are outside."

In this forgotten corner of north-east India, in the foothills of the Himalayas, wedged between Bangladesh and Myanmar, there is a growing sense of nationhood being forged, and of unity amongst a people who have rarely known it.

Historically, the Naga have never been one people. Famously tribal, they were the last headhunters in India, heavily tattooed warriors who successfully resisted domination until deep into the 20th century.

For unknown generations, contact between Naga tribes almost always involved disputes - over land, crops or water - and resolution was almost always the vanquished's head on prominent display outside the victor's home.

Trust between communities that have warred for centuries takes time to develop, and here it is restrained further by the lives most Nagas lead -isolated existences in small villages, separated by craggy mountains and dense forests. Life for many Naga is family, village and tribe. The rest of Nagaland, of India, and of the world beyond, is somewhere else.

But Christianity, introduced by the British in the 19th century, brought with it a sense of a larger Naga identity, while conscription into various armies during the world wars, and the rise of the modern nation state, further strengthened their political will.

On August 14, 1947, the day before India achieved its independence from Britain, the Naga people declared their homeland an independent state, not part of any other country.

In the morning, the powerful new Republic of India ignored the declaration, subsuming all of the land between East Pakistan (now Bangladesh) and Burma (now Myanmar) into its territory.

The Naga have been struggling to re-create that one brief moment of freedom ever since. They feel neglected by the "Hindustan" government in Delhi. Nagaland is poor, and growing poorer. There are fewer hospitals and schools and jobs here than in the rest of India. An HIV epidemic followed a wave of heroin from over the Burmese border, and with it the attendant social ills and disadvantage.

Nagaland, too, has been a violent place. The rule of Delhi has been fiercely resisted. Armed militia have controlled huge swathes of the heavily forested state, recruiting young men, and even children, to their guerrilla campaigns against the Indian military. Factionalised secessionist groups have brawled with each other and targeted minority tribes.

Even the carving out of a homeland - Nagaland - from the existing state of Assam 50 years ago was an imperfect solution. It divided the Naga people between the new homeland state of Nagaland and the neighbouring provinces of Assam, Arunachal Pradesh, and Manipur. Outside India, perhaps a million remained over the British-drawn border in Myanmar.

In 1997 a ceasefire with India was brokered and has, ostensibly, held. But the last few months have seen a return to the violence of previous generations. At least eight bomb blasts have been set off in the Manipuri town of Ukhrul alone by Naga separatists.

Nonetheless, those promoting violent secessionism now find themselves a noisy minority. Most here are tired of fighting.

Recently, after a truck was blown up in a marketplace in Ukhrul, thousands turned out to a candlelight vigil beneath a statue of Mahatma Gandhi. And across the Naga homeland, tribes who have formerly found reason only to disagree, are finding ways to commune. Now in its 14th year, the Hornbill Festival is Nagaland's most significant event, a gathering of 16 major tribes of the state, who descend upon a village near Kohima, in celebration of Naga solidarity.

The 10-day festival draws Indians from across the country, and tourists from all over the world, to the most distant state of this diverse republic. But beyond its place as a money-spinner and tourist attraction, the Hornbill plays a powerful political role in bringing Naga tribes to the same place in peace, the only occasion they do anything together.

"Ordinarily, there is no such thing as a Naga person, we are all our different tribes," the Commissioner of the Government of Nagaland, Himato Zhimoni, explains. "Definitely we are all Nagas, but only when we come together. Otherwise, we are an Angami, or a Sangtam, or a Sumi, or an Ao. And it is only the Hornbill Festival that brings all the different people, from all the different regions that they come from, to one place where we celebrate unity, and the idea of being Naga."

Some in Nagaland fear that the influence of modernisation and development - of mobile phones, K-pop and American television - will erode Nagaland's indigenous cultures. Augustine Shimray is one of the few Nagas to still wear facial tattoos.

Once, both women and men decorated their faces (the men's celebrated successful battles against neighbouring tribes), but Shimray feels as much of an outsider in his own place as he does elsewhere in India. On a visit to his ancestral property - a one-room wooden hut by a river at the western end of a valley - his uncle tells him "you belong in a museum".

Shimray says the traditional harvest festivals and the ancient stories of the Naga tribes are being lost. "There used to be piercing, there used to be special rituals, sometimes three days, to pierce young boys growing up to be men," he says. "The elders who had wisdom used to do it sacredly, but those hands are no longer there."

These days, the Naga find themselves caught between history and modernity, between establishing their own identity and finding a place in polyglot, multicultural India. But in the Hornbill Festival - a celebration of their shared ancestry, and a recognition of all that unites, rather than a focus on that which divides - the Naga have found a path towards peace.

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