Following routes that their ancestors took millennia before them, the Sami reindeer herders migrate across the frozen wilds of northern Sweden.

A cry goes up from the forest. A snowmobile shoots out onto the frozen lake, skirts the trees and disappears. Nasti the Lapp dog – two pointy ears protruding from a mess of black fur – yelps and whines, eager to be on the move. Deep within the trees ahead, a strange whooping and hollering crescendos and subsides, before rising 90 degrees to the left and once again fading to nothing.

‘Ah, here comes my brother,’ remarks Lennart Pittja, looking up from the smoked reindeer meat he has been slicing with a hand-carved knife. Nasti can wait no longer. He bounds across the lake to the treeline, only his tail visible above the snow.

There, a couple of hundred metres beyond him, are the reindeer. They appear as a trickle, a single-file struggling through the deep snow towards us, but are soon pouring out of the forest at a pace and number it’s hard to keep up with. On and on they come, a stew of antlers and hooves and kicked-up snow, the occasional snout poking out above a rolling carpet of fur.

And then, just as suddenly, all is still. The reindeer stand motionless on the lake, sometimes nosing the ground and otherwise looking a little surprised. Nasti perches on the back of a snowmobile, apparently aware that he’s had his fun, and the drone of engines is silenced as the riders gather round for a chat. The first morning’s work of the annual migration is done.

The depth of winter has now passed in the World Heritage site of Laponia, more than 3,600 square miles of pristine forest, mountain and lake in Sweden’s far north, 40 miles beyond the Arctic Circle. For Lennart, the weather is positively balmy. He draws air deep into his lungs and smiles. ‘Ah, it is like the Outback here today.’ It is 15°C below.

A warm hug of a man forever bubbling with good humour, Lennart is the latest link in a chain of reindeer herders that stretches back nigh on six millennia. His brother Kenneth, with the deep voice, long whiskers and imposing girth of a fantasy novel character, is the main herder. Like their ancestors, their lives are intricately woven with that of the reindeer and the land on which they tend them. Theirs is the story of the Sami, the indigenous people of Sápmiland, an area extending over the northern reaches of Norway, Sweden, Finland and Russia – and more familiar as Lapland to anyone who’s ever written a pleading letter to Father Christmas.

‘Every Sami person has a special relationship with the reindeer, it’s difficult to explain,’ says Lennart, gesturing to the 300-strong herd milling about on the lake. ‘Without the Sami, you wouldn’t have this many reindeer, and without the reindeer, there would be no Sami. It’s thanks to the reindeer that we are still here in the north; they let us survive.’

Emerging from the woods where they have spent the last four months foraging for food among the birch and spruce, the reindeer are on their way to summer pastures in the mountains some 200 miles to the west. Here the females will calve and the males will get fat, ready for slaughter in the autumn, before the herd makes the long journey back to the forests for the winter.

The migration takes around 10 days, through marshland, forests and mountains, at a pace dictated by the herd rather than the herdsmen. ‘We are following the reindeer – they set the programme. I have a plan but the only thing I can say for certain is that we won’t follow it,’ explains Lennart as the reindeer move off at a steady trot.

Kenneth is quick to notice if an animal is missing – he knows every single one of his reindeer by sight. He has urged the herd into the family corral at Stubba, a few miles north of the forest, and stands amid a boiling mass of animals in the central enclosure, thoughtfully chewing on a blade of straw. He picks out a small bull with stubby antlers buried deep within the pack, raises his arm slowly above his head and lets the lasso fly. Bingo. The animal bucks against the rope, his front legs struggling to find purchase in the snow as Kenneth hauls him in.

During the summer mating season, uncastrated bulls raunch around like drunk teenagers, fighting other bulls, chasing the ladies, and losing up to a third of their bodyweight in the process. It’s no good to the herders who wish to sell their animals’ meat in the autumn, and the Pittjas are in the corral today to nip the problem in the bud. Kenneth and his son Juvva battle their young reindeer to the ground; with a summary snip of the pliers, its genetic legacy is forever lost. It hobbles away with a slightly wild look in its eyes.

The work is still very much a family affair. Lennart and Kenneth’s father, Josef, stands on the sidelines with their uncle Bertil, dispensing advice and stories. Nephew Emil grapples with a bull, yanking it by the antlers with one hand while taking a call on his mobile with the other. Reindeer skitter around the pen, darting in one direction and then the other, the movement of a single nervous animal setting the herd moving again just as they start to settle.

Despite the frenzy of activity, the lasting impression is one of calm. Voices are raised only to swear at Nasti, who stands well away from the kicking legs of the herd, barking furiously. The herdsmen’s treatment of the animals is firm, pragmatic, respectful. It is part of an approach to life that allows them to flourish in an environment most would consider hostile. The land, even when frozen, is a generous ally, providing food, shelter and warmth if you know where to look for it. Only a generation ago, the Sami would live outdoors with their herd and track the reindeer on foot. ‘But it was tough,’ reflects Lennart. ‘We would survive well without electricity if we had to, but change is not a bad thing.’

Indeed, modern reindeer husbandry comes with such a litany of financial pressures that, without change, there’s a real chance it won’t survive beyond Juvva’s generation. From the EU law that prevents them from slaughtering their own animals and thus getting the best return on them, to competition for land from forestry, mining and hydroelectricity, the biggest threat may well come in the shape of predators, such as the lynx and weasely wolverine, that stalk the northern wilds with a lusty eye on the Sami’s reindeer. These predators are protected species and the Sami are prohibited from hunting them if they attack the herd but, says Kenneth, if a reindeer is killed, the Sami are compensated only 50 per cent of its value by the Swedish government. During the last spring migration, half of his herd disappeared in a single night. ‘We are not part of the economic system – if we lose reindeer, it can take us years to build the herd again. How is Juvva going to survive if he has to give up half his income every year?’ Gloominess seems to sit uneasily with the Pittja brothers. ‘I’m angry sometimes but I am always optimistic,’ says Lennart. ‘We realise it is up to us to keep the culture going, not the government or the EU. We have been here thousands of years so we are not doing so bad.’

The family is nothing if not resourceful, making extra income selling homemade traditional Sami clothing and knives carved from reindeer antlers. Lennart’s own solution is tourism. Since 1995, he has been guiding small groups through Laponia, trekking in the mountains in the summer and joining the reindeer in the early spring. ‘We bring guests out here to share our lives. I don’t know anything about marketing and I’m not a politician but I know people like to come here and they go home and tell their friends about us.’

It is the migration that sees 12 thick snowsuits shuffling about Laponia. Inside the suits, beneath goggles and thermal hats, are Americans, Australians, Europeans – trading their lives as lawyers and doctors to become Sami for five days. ‘I am proud to take you out there,’ beams our guide. ‘You will soon be reindeer-herding experts.’

We are expert at nothing when we arrive at Stubba. Wading through snow the consistency of porridge, we tumble about like giant toddlers. We forget to stay active, and the cold slaps us in the face and stamps on our fingers and toes. We fly off the back of snowmobiles and ditch them in deep snow. Zipped up in our cumbersome snowsuits, we look like astronauts. For all our familiarity with the wilderness around us, we may as well be on the moon.

‘Don’t worry,’ says Lennart cheerfully as he packs the sleighs that carry our food and equipment. ���We will help you to survive. Most people do. Which is a good thing.’

We are several hours behind the reindeer by the time we have cleared the camp at Stubba, pulling down the tepee-like tents, known as lávvu, that are home for the next few days. The snow acts as the herdsmen’s newspaper, telling them where the reindeer are, whether there are predators in the area, and of the presence of clumsy foreigners who have lost control of their snowmobiles. The trampled route we follow is a rolling ticker of information, announcing that all is well with the herd. Here and there, a single line of prints peels off to a spruce tree. Newsflash: a reindeer has trotted off for a snack.

Far in the distance, a neat line moves across the horizon, trailing puffs of cloud like a steam train. The sun is a pale smudge in the sky, a pinhole promise of light and warmth, as we lurch and bump across the frozen land in pursuit. As we draw closer, the neat line turns into a snorting tangle of reindeer, steam from the melted snow beneath their hooves rising above their heads. Lennart, Kenneth and Juvva leap on and off their snowmobiles, waving their arms and whooping to chivvy the animals along.

The pregnant females, in particular, have a strong instinct to keep walking once they clear the lowland marshes and forest and start the slow climb uphill three days into the migration. ‘They can smell life, the mountains, the earth,’ Lennart explains. Kenneth seems to feel it too – he becomes more buoyant the further west we travel.

Before we reach our rest-stop each night, Juvva races ahead to cut down a few trees so the reindeer are better able to pull off the wispy beards of lichen that hang from their branches. If it has food, the herd is happy to stay where it is for the night; if they grow hungry, the reindeer set off for the previous night’s camp, forcing Kenneth to backtrack several miles each morning to round them up again.

Keeping reindeer herders in the same spot overnight is an easier proposition – sit them on reindeer fur by the fire and feed them reindeer. Minced reindeer, smoked reindeer heart, smoked reindeer tongue, barbecued reindeer steaks, cured reindeer leg, reindeer with pasta, reindeer stew scooped from a blackened pot. Gathered in the lávvu, evenings pass with the Pittja men sharing tales of peril and romance, hope and fear in the candlelight.

‘We’ve had language for a long time but not the written word,’ says consummate storyteller Lennart. ‘It’s a spoken language so talking and sharing stories is the Sami way to read a book.’

The Sami language is extraordinarily eloquent when it comes to the natural world. While there are no words for ‘terrorist’ or ‘credit crunch’, there are more than 100 for snow, to denote levels of grip and depth and texture, and over 50 for reindeer.

‘With only one word, I know what the mountain looks like, what the condition of the snow is, how the reindeer are,’ says Lennart. ‘And Sami is much better for swearing than Swedish. Swear words in Swedish are like a mosquito, in Sami they are like a golden eagle.’

Being with the herd and in that environment is a delight that loses none of its novelty. Just as spirits start to flag from cold, some astonishing new spectacle presents itself.

As we near the end of a long day, the setting sun catches loose snow whipped across the surface of a frozen marsh by the wind, golden flecks whirling in the deep-blue light of dusk. A sleepless night spent rigid on the frozen ground inside the lávvu is instantly forgotten as dawn brings a group of fearless reindeer snuffling up to the tents, curious and hungry. The following evening, stuck crossing a mountain in a white-out and unable to separate sky from snow, the mood darkens as the temperature drops. But, like an Arctic superhero bursting from the milky gloom, there is Kenneth on his snowmobile, slicing a route down the mountain that takes us below the treeline. We are soon back in the forest of our Swedish fairytale, bouncing beneath spruce branches balancing fat, twinkling pillows of snow.

The white weather had eaten the mountains but I know them so well, I could feel my way down,’ Kenneth tells us that night, stretched out by the stove in a herder’s cabin built by his father.

Lennart is quick to agree. ‘I know the lakes, I know the rocks, I know the creeks, I know the trees. There is no wilderness for me here. This is my garden.’

We are beginning to see this ourselves, caught under the spell of a land that but four days previously had seemed impossibly, comically unyielding.

We return to the mountain in the spectral light of a slow-coming dawn. Up and up we go, squinting into the low cloud for signs of the reindeer we were forced to leave during the white-out. Scattered specks hove into view, gaining legs and antlers as we draw nearer. The herd has survived the night.

Kenneth circles the slopes in everdecreasing loops to gather his reindeer, scooting down the hill to collect animals nibbling on lichen in a copse of birch.

We join the procession for a final time, falling in with the reindeer’s steady plod. Far to the west, across a landscape of frozen valleys and peaks, lie the mountains that will mark their journey’s end. We stand and watch as man and beast march on through the land they have called home for thousands of years, until the herd grows fainter and fainter in the pearly haze, and finally fades into white.

The article 'In Sweden, a long journey home' was published in partnership with Lonely Planet Magazine.