The following correction was printed in the Guardian's Corrections and clarifications column, Friday 24 April 2009

The article below, in which Erwin James recounted his experiences in the Foreign Legion, contains information which is untrue. James was in the Foreign Legion for a time but his claim to have served with one of its regiments in Beirut in the summer of 1982 was false and a paragraph, which purported to describe his experiences there, was fiction. He did not join the Foreign Legion until the end of 1982, by which time his regiment had returned from Beirut. The article also suggested that James accompanied his regiment on missions to Djibouti and the Central African Republic. While these were regular regiment duties, James did not go there. He did, as he said in the piece, go to Chad. In a more recent article James said he joined the Foreign Legion in 1981. That was also untrue. In both articles, we should have made clear that names and/or nationalities of some individuals had been changed so that they could not be identified (Legion of honour, 13 January 2006, page 8, G2, and 'God help anyone who weakened': my life in the French Foreign Legion, 25 February 2009, page 2, G2). The readers' editor will write about this in her weekly column on 27 April 2009).

"Being a legionnaire is easy," said the captain, "and being a civilian is easy. It is the change from being a civilian to becoming a legionnaire that some find difficult." It was a month since I had walked into the recruitment office of the Légion Etrangère in the heart of the Citadelle in Lille, northern France. The night before, I'd got drunk on cheap wine and fallen asleep in an alley. A kind soul had thrown a piece of old carpet over me which had protected me from the heavy January frost and probably kept me alive. Grimy and bedraggled, I limped out on to the main thoroughfare to enlist in my new life.

I had spent most of my last few borrowed pounds on a ferry ticket from Dover to Calais and then jumped a train to Lille before blowing the little money I had left on the wine. After leaving behind a trail of devastation, and the prospect of many years in prison in Britain, I had come to France to join the Foreign Legion.

Reading the reports last week about "flabby" British recruits being put to shame in the Legion by battle-hardened eastern Europeans, I had a sharp pang of nostalgia. For I remember how grateful I was as a young man, many years ago, when the Legion offered me the chance of a way out of deep trouble. I had led a reckless and undisciplined life, and was in very poor physical and mental condition. Most of what I had heard or read about the Legion had left me feeling that it was a place where only desperate men would go. Well, I was certainly desperate.

It was 5.30am and still dark as the captain, flanked by a sergeant and three scowling corporals, continued his welcoming address. He had already given our sleepy-eyed group, his latest batch of "engagé voluntaires", the same speech in French, Spanish and German, his native tongue. We learned later that he was fluent in nine languages. My section, 40-strong, had arrived at the Legion's basic training camp in Castelnaudary, close to the Spanish border, from the selection centre in Aubagne in Provence the day before. Potential recruits are shipped from recruitment posts around France to Aubagne every day. Three weeks of rigorous physical and psychological assessments follow, including interrogations by members of the Legion's secret police, the Deuxième Bureau, hunting for criminals on behalf of Interpol. We were told that only one in 12 applicants made it to basic training.

Before leaving Aubagne we had each been given new equipment. On that first morning at Castel we were ordered to lay out our kit neatly in front of us on groundsheets, ready, we thought, for the captain's inspection. "We are going to help you make the change," the captain continued, "but you will have to work very hard." Without warning the corporals began kicking our shiny new kit in all directions. Soon, mess tins, uniforms, bars of soap and boots were all mangled and mixed up together in unruly piles.

A Chilean recruit named Garcia, with whom I'd become friendly at the recruitment station in Lille, swore in Spanish. Two of the corporals raced at him and began screaming into his face. "Seulement français! Seulement français!" They pushed him to the ground and screamed again, "Allez! Pompez!" Garcia was made to do push-ups while we gathered our stuff together. Then we were ordered back to our billet to change into PE kit for the first of what were to become regular dawn runs. Garcia was still struggling with his push-ups when we returned, exhausted, an hour later. Our first lesson: on no account were we allowed to speak anything other than French, even when we swore.

Our instruction was to last for four months. The men in my section were in various states of fitness when we started out. Several had had some previous military experience. One, a Frenchman who joined claiming to be Swiss (apart from the officer class, French citizens are barred from the Legion and join in disguise), was rumoured to be the disgraced son of a French regular army colonel. His discipline and informed understanding of military ways indicated that there might be some truth in it. On the whole we were a motley crew: some tall, some skinny, many flabby, a few who were quite fit.

Around half the section were French. There were a number of Germans, a man from Iceland, another from Sri Lanka and one other Brit. I made some friends: Garcia, who sang and played the guitar he'd brought with him from Chile; Max, a bankrupt Austrian dentist who spoke flawless English; and Henni, a former marathon runner from Morocco. We formed strong bonds as we marched through the foothills of the Pyrenees, shot at targets on the rifle ranges with our Famas 5.56s, and broke the ice for weekly swims in the local reservoir - relentlessly urged on by the corporals, one of whom, a big Tahitian, had only one eye but could shoot his rifle more accurately than anyone else in the regiment. We were taught about Camarone, a celebrated battle where 60 legionnaires fought to the last man against several thousand Mexicans in 1863. We were punched and kicked, made to dig holes and then fill them in for no discernible reason, and regularly dragged out of our bunks in the early hours and made to march and sing around the quadrangle under floodlights. (Singing while marching is a great tradition of the Legion - and an ingenious way of learning French.)

And we undertook the "képi march", the hardest task of all. The trek lasts for four days and nights, through the Pyrenean foothills, during which we stopped only for brief moments of respite and sporadic bouts of sleep. When it was over, we lit a huge bonfire and drank wine and sang our Legion songs until it was time for our captain to present each of us with our képi, the famous Legion white cap. "You must wear it with honour and fidélité," he instructed. "A vos ordres, mon capitaine!" we replied in chorus. By then, the differences in our backgrounds, or the condition we'd been in before, had little relevance. Those of us with the will (in my case, the desperation) to succeed had been taken in, revitalised, reprogrammed and finally regurgitated as fully fledged legionnaires.

There were 28 of us left in the section at the end of the four months (nine had deserted and three were hospitalised and medically discharged). Those of us who remained were fitter and healthier than we had ever been in our lives, and as close as a family, an ideal that the Legion deliberately sets out to achieve - "Legio Patria Nostra" is one of many Legion mottos, which roughly translates as "the Legion is our homeland". We had been turned from a band of straggling strangers into a tight unit of formidable soldiers, brothers in arms basking in our reputation as fearless and feared warriors, and eager for whatever adventures lay ahead. Yet many of us cried at the station as our captain bade us farewell and "Bonne chance" on the platform at Castelnaudary station.

From Castel we were dispersed to regiments around the world: Djibouti, French Guiana, Tahiti ... some went to regiments in mainland France. Max went to work in the Legion's administration dept in Aubagne; Garcia, Henni and I were dispatched to Corsica to join the 2ème Régiment étranger de parachutistes - the Legion's only parachute regiment. We took the ferry from Marseille to Ajaccio, proud to be mixing with passengers in our khaki summer uniforms, our new kepis gleaming in the May sunshine.

We had learned about the 2nd REP during basic training. It was a regiment with a glorious history, renowned for operations in Algeria, Chad, Somalia and many other trouble spots across the world. We joined the promo (the parachute training class), where seven others who had arrived the week before us were waiting along with two corporals and a Polish sergeant, a Kolwezi veteran, who would be our instructors for the next three weeks.

Our new teachers were fiercer and even less forgiving than those at Castel. Getting us out of bed in the early hours to don parachutes and jump off bedside lockers was a favourite jape. "Allez! Saut!" Loading our Bergens with rocks for the "sac à dos", the 8km run with full pack, was another. "Vite! Vite!" they screamed. It was a relief when the time came for us to jump for real from a Transall C160 transport plane. Henni twisted his back on only his second jump; he was sent to the mainland, after which we were told he was medically discharged. Every other member of our promo graduated as parachutists and were awarded silver wings to wear on our breast pockets, complementing the rest of the "guidy guidy" (regimental badges and lanyard.) We celebrated with wine and songs and Garcia and I were allocated to the 1er Compagnie Commando. Two months later, in summer 1982, we were in Beirut, helping to keep the peace.

I had heard that before the 1982 invasion Beirut had been known as the Paris of the Middle East. It could still be imagined, though its wide boulevards and once beautiful buildings were now pockmarked with rocket craters and holes drilled by heavy machine gun and small arms fire. Our section was based in the west of the city, bunkered in an old brandy warehouse. We met American marines and Italian infantrymen, and talked weaponry. We had no politics. Our only allegiance was to the Legion. But it was hard not to feel for the plight of the civilian population. We stood by as open-backed land cruisers, heaving with laughing, keffiyeh-wearing Arab soldiers firing Kalashnikovs, hurtled through the streets to their evacuation. Many of us had never heard gunfire before that was not our own, but nobody gave any indication that they were afraid. The eternal sunshine and clear blue sky seemed to shed an incongruous light on this battle-scarred city.

The mission in Beirut complete, we returned to Calvi to be presented with our Médaille d'Outre-Mer (overseas medal) and Médaille Défense National. We were "bluebeats" (novices) no longer.

From then on we spent our time training - endlessly. The regime was full and rigorous, with every type of sport or hobby available, but living in constant anticipation of a mission d'outre-mer could also be tedious. Drinking cold beer by the case was a favourite pastime. Some people got bored and got drunk; others got bored and deserted. A 25-strong contingent of Brits, known to the rest as "le mafia anglais", dominated the Foyer (regiment bar) at weekends. Whenever there was a bordel (violent occurrence), invariably members of the British mafia would be involved.

Patrol missions to the former French territories of Djibouti and the Central African Republic were regular duties of the regiment. Tours of duty lasted four months and were routine. Occasional border incidents, attempted incursions or territorial disagreements provided moments of excitement, but otherwise our purpose was simply to provide reassurance that France would always ensure stability in the region. A bonus was that, for the period in which we were in Africa, our pay almost doubled. When the tours were over we returned to Corsica to enjoy three weeks of leave, before settling back into a life of constant preparation and training. I found that being a legionnaire presented an ordered way of life that offered the possibility of redemption from past sins and failures. For me, it was the family I had never had.

When, in 1983, the orders came for us to go to Chad to support the Chadian government against Libyan-backed rebels, we expected real conflict. "C'est la guerre" echoed through the camp, a mixture of excitement and anticipation of serious conflict. It turned out not to be the case exactly - there was a war, it just wasn't our war. We spent weeks travelling through the desert in Willis jeeps and French camions, stopping every few days. When most of a platoon of French regular soldiers were killed after disturbing a booby-trapped tank, our section cleared up afterwards. But we loved being legionnaires in the desert. For young men like me, who didn't really belong anywhere else, it was like being given a home.

After a few weeks in Chad, during which I spent my time mounting desert patrols and escorting PoWs, trouble flared in neighbouring Cameroon. My section spent the night sitting, back to back, on the runway of the capital Ndjamena, another once beautiful French colonial city, weighed down with arms and ammunition waiting for the order to jump on rebels who had taken Cameroon's airport. Our captain told us it was likely few of us would return. To a man we were willing to give our lives to the Legion. But that didn't stop the wave of relief when the order never came.

They say your past has a way of catching up with you. I used to wonder if it would. Four months later, on my last day of a week's leave in Paris, I heard a banging on the window of a restaurant as I passed by. It was Garcia, who had been sent home after being wounded in a firefight in Chad. He was still bandaged and in pain, but grinning broadly. "Hombre!" he shouted. It was good to see my friend. That night we drank beer and Garcia played his guitar.

Four days later I was arrested and never saw any of my comrades again. But I never forgot what I gained from my Legion experience. It got me through the difficult times that were waiting. If Brits are failing in basic training now, it's not because they are not in good condition. It's because they don't need to be there badly enough.