It is late afternoon. A perfectly calligraphed banner is suspended over the dry dirt road: “Bienvenue à Cange, Régine et Win, Arcade et Fire.” We are all both touched and giggling a little bit. Formerly a dusty, barren hill, Cange now looks like a surreal, lush, medieval village grown out of the Haitian mountains.

The trees that were planted 25 years ago when the NGO we work with, Partners In Health (PIH), began work here have now grown into a landscape hinting at Haiti‘s luxurious forests of the past. But Cange – PIH’s headquarters in Haiti – is definitely one step into the future as it springs out of dry mountains, organised, filled with Haitian nurses and doctors, electricity and paved roads. You can see that the town has been built in phases over the years, up and down the hill, in and around large medieval-looking metal gates. This makes Cange’s unusual charm.

This is my third time here, but our first as a band. As we unload the equipment I can’t stop noticing how they really pulled out all the stops to welcome us. On the dusty soccer field the town has built a wooden stage, with another crafted and charming “Bienvenue à Cange, Régine et Win, Arcade et Fire” banner hanging above it. Knowing how few resources there are in the Central Plateau, it is becoming clear that this evening is a really big deal. We are happy to see the sound system we rented from Port-au-Prince has arrived in time. It is probably the biggest sound system the town has ever seen. Or seen at all. This is exciting.

We plug the instruments in, but there is no power. The Haitian soundman goes to check out the gas generator. It hums back to life and everything powers up fine. To be honest, the monitor set up here sounds better than what we had on the Funeral tour. But now a dark rain cloud is approaching and we feel a few drops on our heads. The rented equipment is too precious to risk, so we pull out big white tarps and cover it up with the help of staff from Partners in Health.

In the meantime, a small bus enters through the Cange gates. RAM is here. We have played with this Haitian band a few times now and we are happy to see that they, too, made it safely on time. They opened for us once in Quebec City, but here in Haiti we are definitely the support band. Caribbean showers rarely last for long. So we decide to take the opportunity to all go for dinner.

We walk down the hill to the small community centre that is the one room large enough to accommodate us all. I can tell that the cooking staff have been working all day, if not all week, in preparation. The table is set for a banquet. Goat and chicken, plantain, two kinds of rice, salad, rum cake… Last time we were here, it was rice and beans for lunch and peanut-butter sandwiches for dinner. One of the staff tells us a story about a funeral for a young man that had taken place a few days earlier. During some recent funerals people had become so riled in their grief they’d broken several metal folding chairs (at around 500 Haitian gourdes or £7.60 each). The priest, Father Lafontant told everyone during the last eulogy that anyone breaking a chair during the service would have to pay for it, and sure enough he had to point to two people during the service and yell out: “Cinq-cent gourdes!”

It was last summer when we invited RAM to Quebec City to play with us at a festival. Over that weekend we became friendly with many of the group. I remember eating dinner in the catering area and noticing one of them had a distant look on his face. I realised he was looking at the festival’s catering tent, which was bigger and nicer than the one he lived in. Many of the musicians in this amazing band are still living in tents in Port-au-Prince, more than a year after the earthquake.

I am grateful that they are with us tonight. As part of the evening programme we also invited a man called Ti Zwazo (Little Bird) to come and sing for the crowd. He is a part of Zanmi Agrikol, PIH’s agricultural project. Back in 2008, as we were visiting his sapling farm, he sang two of the most beautiful songs I’d ever heard. Joan, a PIH staffer called him the day before and left a message on his mobile. (Everybody has a phone in Haiti. They might not have a house or enough to eat, but somehow phones spring up everywhere.) Little Bird called back leaving a most solemn message: “Hello. This is Ti Zwazo. I understand you need my services to sing at a concert tomorrow night. Thank you for thinking of me. I would like to notify you that it will be my pleasure to perform at your concert. Merci et au revoir.”

The fancy French expressions I hear around Cange amaze me. Brought into a 2011 context, they turn any mundane conversation into sophisticated 18th-century court talk. It blows my mind to hear a 13-year-old ask me about the simplest thing using language that probably would have appeared normal to Shakespeare. It is surreal. I love it.

Ti Zwazo arrives, all shaven, in a pressed shirt and tie – quite a change from the second-hand T-shirt and straw hat he was wearing when we met him three years ago. Has it been three years? He stands in a corner, all shy. I get off my seat and insist he comes to sit and eat with us. Ti Zwazo’s face is the one of a rugged middle-aged farmer, his eyes are sharp with wisdom, but in this unfamiliar context he sits down and eats silently like a timid schoolboy.

We all walk back up the shady hill. The sun has reappeared after the rain and is now setting. A crowd has started to form. On the opposite side of the stage is a stone wall and a winding concrete path that goes all the way up to the top of the mountain where sits the church of beloved Father Lafontant. People keep pouring in through the gates. They are sitting on the walls, their feet dangling. Now the scene is starting to look like a Préfète Duffaut painting. We don’t want to spoil the surprise so we do the quickest soundcheck ever. The soundman is the same one who mixed our small show in Port-au-Prince two nights earlier, so he pretty much knows what to do with us now.

The sun has finally set. John, one of PIH’s few non-Haitian staff arrives with yellow construction lamps as makeshift stage lighting. The evening is about to start. Down comes the night’s busy bee, cheery and driven Marie-Flore, the daughter of Father Lafontant. She’s the one behind all this welcoming protocol: “We need you to go on stage and stand in line please. Somebody is going to introduce you.”

So we do as we’re told. The next minutes look like a surreal inauguration. The youth of Cange has formed a marching band and is walking towards us. “Ladies and gentlemen, please welcome from Canada, Arcade and Fire. Please, clap for Régine, please clap for her husband Win, clap for Tim, clap for Jeremy, clap for Richard, clap for Sarah, clap for Marika, clap for manager Scott! And now allow us to play for you the Canadian national anthem!”

You’d have to have a heart of stone to remain unmoved by the gigantic effort this community had put forward. I notice that the students are playing the very instruments Win and I brought them last August. “They’ve gotten so good!” I whisper to Win. I can’t believe how much they’ve improved! They must have been practising a ton!”

“And now, please oblige us as we play our own anthem, La Dessalinienne!”

After the honours, we step down and it’s Ti Zwazo’s time to take the stage. He could have a band, but he doesn’t need one. His voice is pure gold and reverberates off the stone walls across the soccer field. In true troubadour tradition, he sings about this evening, about tonight, he sings about us arriving in Cange, about the need for the country to come together, Haitians and non-Haitians… “For all farmers here tonight! You here?” The farmers cheer. “For all the mechanics here tonight!” Mechanics cheer. “We’ve got to put our heads together, for a better Haiti…” And as his powerful song comes to a finale, his last soaring note is drowned by thunderous cheers. I wonder how many other Ti Zwazos this country holds, singing alone in the night when the lights are out.

We then take our instruments and launch into “Keep the Car Running”. Some of the people who were sitting back by the stone wall hop down and come to the front. The first song goes well. This is a good crowd, considering the town has never had a concert of this kind, never mind a rock concert.

We’re happy to see people appear genuinely happy about the music. So we play our hearts out. No super fans, no journalists. Just us, the townspeople, Ti Zwazo and RAM. As we play the song “Haiti”, I invite Philemond, one of the older youths of Cange, to come on stage. In 2008 he sang the song with Win and me, and has learned it on the guitar since. We’re out of guitars, but it doesn’t matter. He starts to sing front and centre and leads the singing crowd.

Surprisingly, everything sounds good on stage. No feedbacks, everything is clear. We definitely have had worse sound in fancier places. By the end of the show a good number of people are jumping, hands in the air, all smiles. I think we’ve made new friends.

As we walk out, an 11-year-old boy runs up to Win, eyes as big as dollars, wearing the widest grin. “I just want to tell you… I will never forget you my whole life!” he says, then vanishes. Marika also has a new friend. Raoul, a studious 12-year-old orphan who is the town’s number-one student in all fields, especially mathematics, is following her everywhere. Marika taught high school for five years, so she takes an interest in his curriculum and favourite classes.

Meanwhile, between the two sets and a bit of Haitian-style DJ-ing, PIH’s Haitian peptalk man jumps on stage to MC a little: “One more round of applause for Arcade and Fire! Come on! Arcade and Fire ladies and gents! They play North America! They play South America! They play Europe! They came on a plane! They came on a boat! They came on a bus! They eat mango! They eat rice! And now they are here to play for us tonight!”

The crowd cheers. Pepman then goes into the most clever cholera prevention song I’ve ever heard. Using Creole’s percussive rhythm he chants: “What do you do after this and that?” The crowd answers: “You wash your hands!” “Put your hands up in the air! Let me see those hands! Now after this, what do you do?” “Wash your hands!” “And after that, what do you do?” “You wash your hands.” “That’s right!” he answers the crowd each time. “You wash ’em. You wash those hands!” Hands are waving as if we’re at a hip-hop concert.

His spiel then turns into a stand-up comedy act where he pretends he’s a man struck with tuberculosis who’s come home coughing, but keeps pretending to his wife (acted by him putting a hand on his hip and talking in a high voice) that he’s all right. The crowd laughs. “Now what shall we do with a fool like that?” The crowd answers in a blur: “You send him to the hospital!” “I didn’t hear you!” “You send him to the hospital.” “You send him where?” The crowd replies in unison: “To the hospital!” “Good… and now ladies and gentlemen, let me introduce to you the great band RAAAAM!”

RAM comes out, all dressed in voodoo white. I wonder what Father Lafontant might think of all this. RAM plays mizik rasin – roots music. Their exuberant style draws on various voodoo rhythms and their lyrics and inspiration call on folklore and lwas – the deities or spirits that are said to have originated all the way from ancestral Africa. A very contrasting style to Cange’s sweet and gentle church choir. Either way, the band and crowd, old and young, are all in good spirits. More watchers come down off the walls to get closer to the action.

I watch a few songs, but then remember we are leaving the next morning at 7am, so there are a few things I want to settle. On the side of the stage is the dusty library/soccer equipment storage/backstage area where we keep the 20 hockey bags we have brought to Haiti. (We’ve brought as many as the airline would allow us. They are filled with musical instruments, their extra parts and accessories, hospital sheets and other things.) Win is telling me to come out on to the field and have fun, but I really want to sort out the instrument distribution so that everyone ends up with the right combinations.

“One electric guitar and one amp to the community leader in Kay Epin, because they have a little electricity there. Wait. No. Yes. One here. And one there. The accordion and the three acoustic guitars go to the three churches of Bay Tourib. The bass to the Cange bandleader… One guitar for RAM.” Making piles, making piles. Making sure to include the right strings for the right guitars and not forget anyone.

The party is now raging outside. It’s dark. The dusty library is hot. I’m unpacking and repacking every hockey bag under the harsh white fluorescent lights. Win finally comes in in a fast swoosh, stops, and says sweetly: “Enough with this, I order you to come out now!” I walk out, looking backwards… but after a few seconds, I forget about the hockey bags. The whole town is jumping and wailing for RAM. Children, patients, doctors, teenagers, even the elderly. The entire community has surrendered itself to the music.

All that dancing in the dirt is churning up a beautiful cloud of dust that engulfs the whole scene under the home-made stage lights, adding to the surreal atmosphere of the evening. So much joy is everywhere… In these mountains, where nights are so dark, strangely, it feels like we’re all dancing in broad daylight.

Patients have walked down from the hospital. Some on crutches, some in casts, some still wearing hospital masks. The elderly are dancing with children. Toddlers are imitating the adults. It seems the whole town has been given a chance to shake out their woes for one night, and for once enjoy a little more than the bare minimum needed to survive.

I look at Richard, who looks like he’s leading a full-on aerobics class. A swarm of five- to seven-year-old schoolgirls are imitating his dance moves. One of those little girls, in Sunday dress, grabs both my hands. We dance and dance and dance. She’s like a little white butterfly. I make her twirl and twirl, but she always grabs my fingers right back tight with her tiny fingers at the end of each turn. She will not let me go. Finally, I invite some of her little girlfriends into the circle so we can all dance together.

We’re getting towards the end of the set and Richard Morse from RAM signals us to join in during the last song. We climb back on stage, one by one, as soon as we notice the call. As I join in, dancing with the women on stage, I turn around to see that the rest of the guys have each been handed a big rara carnival horn. Tonight might as well be carnival, I’m thinking, as the show ends on this blissful, high-spirited note.

Instantly, people start to go home. Little Miss Butterfly runs back towards me. Her older sister is behind, dragging her by the arm as she’s still trying to grab me. I find myself standing in the middle of the fast-emptying field with the rest of the band and PIH staff, all covered in dust, eyes sparkling, reflecting on the beautiful night that has just happened. Miss Butterfly has sneaked back again. I tell her sweetly in rusty Creole that she should really go back, or else her sister will be very worried. She doesn’t say a word, but keeps hovering around the adults. Oh, tiny night-time butterfly! It is definitely past children’s bedtime. I wait a few minutes more, then switch to, “Cherie, you have to go find your sister now, or she will be very angry!” This new wording seems to resonate with her. She hurries away.

Although, in my heart I never believed it, I had wondered at times if all that excitement could have turned into trouble once the night was over, but I watch thousands of spectators file out in the most serene fashion. Once the field has cleared a little, one man who had come on a motorcycle does a couple of stunt turns for his peers. I worry for a second as a Haitian security guard approaches, reaching in his pocket, only to take out a cell phone and start filming the acrobatics with one hand while shooing curious children away from danger with the other. Stuntman’s flamboyant departure sends out the last clamour and clouds of dust into the night. After that, everybody goes home and the town becomes quiet.

I wonder how far people came. I heard some of them drove for hours, although most seem to have come by foot. But where are they now?

They all vanish into the mountains. Those mountains which, more than two centuries ago, cradled the Haitian dream for liberty and provided shelter for the brave rebels who categorically refused to live in slavery, sparking the Haitian revolution – the only successful revolt of its kind in history.

Outside the gates of Cange, there is a newly built road that now leads all the way from Port-au-Prince. Thousands are walking to their mountain dwellings in peaceful silence and the only sound I hear is a lonely nocturnal rooster. A distant echo. In the rural mountains the moonlight seems thinner than usual, but Haitians have long mastered the art of finding their way in the dark.

Arcade Fire play Hyde Park on 30 June. For tickets, go to livenation.co.uk/Arcade-Fire

• This article was amended on Sunday 19 June to correct the name of the writer in the standfirst