Lineta Miseikyte is only now recovering from the Battle of Austerlitz. I met up with her earlier this month at Dine, a snazzy Vilnius wine bar. Lithuania , she told me, has been making films for years. Usually it plays the role of Russia, although it’s also been Tudor England (Elizabeth I) and even Sherwood Forest (Robin Hood). Lineta, now a production manager, is an old hand in the business, but it’s War and Peace, the BBC’s latest commission, that visits her at night .

“It was so complex! They had a list of a hundred locations: country estates, battlefields, Moscow, palaces… A few scenes were shot in St Petersburg, but for the other 17 weeks they were here and in Latvia . We had to make more than 1,000 costumes, and at 'Austerlitz’ there were 300 extras on set for 10 days – plus 40 horses! And it was only a sheep farm with a muddy track for all our trucks…”

Lineta laughed. “Easy. You only need to drive out of town and it looks like 1812.”

I began my tour of the 1812s – both old and new – in Riga, the best place to appreciate the magnificence of these two small countries. Latvia and Lithuania are each only half the size of England, and yet, at various times, they’ve enjoyed conspicuous wealth. I only had to step out of my hotel to be enveloped in pastel and art nouveau. This, it’s said, is the “Paris of the North”.

Riga: Paris of the North Photo: AP/FOTOLIA

The scent of old commerce – pine, wax and resin – still lingers over the city, and down in the market they sell badger pelts and enormous hairy skins. Rigans even make a special drink, Black Balsam, that looks and smells like Baltic pitch. I once saw an advertisement for a shooting range (“Try our Kalashnikov!”), and so I rang the number. “Sorry, can’t speak now,” came a woman’s voice, “I’m in the forest, hunting.”

"The landscape became so flat and frozen that I could almost make out the curve of the Earth, defined in snow" Photo: AP/FOTOLIA

I’d have been happy to stay for weeks in such a sumptuous, red-blooded city, but before long my driver, Aldis, appeared. He would drive me down to Latvia’s southern border, a task of about an hour. But although the journey was short, it was rich in anecdotes and spectacle. The landscape became so flat and frozen that I could almost make out the curve of the Earth, defined in snow. Aldis told me that the oak trees – now filigreed with frost – had magic properties, that his family had farmed this land, and that the Soviets had sent them to Siberia for owning eight cows.

• St Petersburg in winter: 'Like stepping into a Russian novel'

We parted at Bauska, near the Lithuanian frontier. Nearby was the first of the BBC’s locations, the Rundale Palace. I don’t think I’ve ever seen such a startling structure: a vast, saffron-yellow Versailles. Its construction, beginning in 1730, had involved 1,000 artisans, and – each day – 433 wagon-loads of materials (including three million bricks, 15,000 planks and 36,000 saplings). Eighty-two years later the real Napoleonic army appeared, and you can still find the names of the French soldiers gouged in the plaster of the Gold Hall.

"I don't think I?ve ever seen such a startling structure: a vast, saffron-yellow Versailles" Photo: AP/FOTOLIA

It took me most of the afternoon to wander, slightly dazzled, through its 40 state rooms. Despite a history of rude intrusions (Napoleonic, Nazi and Russian) and a short spell as a Soviet granary, the 18th century had somehow reappeared. Here were Chinese vases, brocatelle wallcoverings, ostrich feathers and cupids firing muskets. I even spotted an original Liotard, and a tiny secret compartment where the countess kept her maid. It was perfect for War and Peace, and the Natashas and Nikolais had been here for a fortnight.

"Eighty-two years later the real Napoleonic army appeared, and you can still find the names of the French soldiers gouged in the plaster of the Gold Hall"

Rather less opulent were Rumsisk es’ farmsteads, across the border and two hours south. I had a new guide now, a Lithuanian called Linas. Amusing and generous, he was a peerless advocate for his country, for Baltic holidays and for the eating of pigs’ ears. Rumsiskes, he said, was used for all the country scenes, and the bits involving peasants. But it was also beautiful in its own way: a collection of old buildings from all over the country – including windmills, churches and hives – now rearranged over a scattering of hills.

From now on, there was always more war than peace. In June 1812, Napoleon had reached Kaunas, and, from a point high on the banks, he’d watched his Grand Armée crossing the Nemunas. Two centuries on, we climbed the same little hill (Napoleono Kalnas) and, way below us, the river snaked through the city, steaming in the cold. Happily, Kaunas had recovered from its battering, and was now all spires and pantiles again.

Kaunas: all spires and pantiles Photo: AP/FOTOLIA

It was even better close up, if slightly eccentric. Among the Gothic buildings and spires, I found statues of trolls, and a Museum of Devils. Meanwhile, the old baroque square was being overwhelmed by a Christmas tree so enormous I could walk around inside. Linas also took me to a funky little doughnut shop (Tres Baltes Kaves) left over from the Seventies. Elsewhere all trace of the Soviet era had been removed, except the carcass of a concrete hotel. Across the top, someone had daubed the longest word in Lithuanian. It translates as “You will not be able to pick the bunny cabbage anymore”.

“Napoleon lost 11 days in Kaunas,” said Linas.

I must have looked puzzled. “This was an outpost of Imperial Russia,” explained Linas, “so it was the Julian calendar on one side of the river, and Gregorian on the other. A dateline!”

As we sped west, I was reminded of all the other things Napoleon had lost on the road to Vilnius. That morning, the landscape was sparkling with frost, and we could see men fishing on a frozen river. It was a scene of Bruegelesque beauty. But back in June 1812, it was scorching, and Napoleon’s cavalry was baked in the mud. Without even a whiff of battle, 10,000 horses were lost.

• Borodino: where Napoleon won and lost

We stopped only once, at Trakai. Suddenly, the sky was filled with another stupendous structure – this time a crimson castle, on an icy lake. In the summer, said Linas, you could rent a cottage and spend a week boating through the islands. Movie-makers love it too, and all sorts of baddies and Tudors are always bursting through the walls. But it was too red-brick for War and Peace, and was only used for a menacing indoor scene. Even that would have puzzled Napoleon because, when he marched by, the fortress was in ruins. It would be rebuilt much later, by the Soviets.

"With its cobbles and gas-lamps, Vilnius already feels like a film set. The BBC crew are said to have loved it here, and rented 30 apartments"

I spent my last few days in Vilnius. In War and Peace, it doubles as Moscow and several other grandiose cities. It’s not hard to see why. Although it’s only small, and the old parts are easily covered on foot, it’s bewilderingly regal. Compacted over a couple of hills are a dozen baroque churches, several monasteries, some ramparts, a university and a cathedral that looks like the Parthenon. With its cobbles and gas-lamps, Vilnius already feels like a film set.

In War and Peace, Vilnius doubles as Moscow and several other grandiose cities Photo: AP/FOTOLIA

The BBC crew are said to have loved it here, and rented 30 apartments. It’s easy to understand their contentment. Café society is booming in Vilnius, and its people seem endlessly theatrical. They love dressing up and eating out, and have a quirky sense of design. Look out for the giant tattoo parlour on Literature Street, and the false teeth embedded in the wall. For the Beeb’s producers, only the filming was hard. “We ran out of snow,” said Lineta, “And, God, did the horses s---!”

For Napoleon, Vilnius will have held less happy memories. I recognised the town hall from a print of him, in full retreat. By December 2012, he was back in the city, filling the churches with his starving men. The writer, Stendhal, had a billet on Didzioji Gatv ee (above what’s now the bookshop), but most froze. A few years ago, contractors found another 2,000 Frenchmen curled up under the woods. Napoleon had entered Russia with more than half a million men, and would leave with just 10,000.

"For Napoleon, Vilnius will have held less happy memories. I recognised the town hall from a print of him, in full retreat"

On my last day, Linas drove me up into the forest, above the city. There, deep in the snow, we came upon a tiny stately home, painted yellow. It was all made of wood, and had once been the home of Pushkin’s son, Grigori. It was a splendidly thoughtful place, full of dark imperial furniture. Although created 50 years after the events in War and Peace, the BBC still used it as a set. For me, it would have been perfect for that scene with Napoleon, brooding over his folly.

Poor Boney, there was a lesson here that he (like others) would learn too late: enjoy the Baltic States, go everywhere and eat everything, but best leave the troops behind.

Essentials

John Gimlette travelled as a guest of Baltic Holidays (0161 860 5248; balticholidays.com), which offers tailor-made tours of the region. A seven-day War and Peace tour costs from £662 per person based on two sharing on b&b basis. Price includes flights, four-star accommodation, guides, day trips and transfers. A more extensive two-week tour costs from £1,850.