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Bbc Sounds, music, radio, podcasts. At 8:59 AM, on the 19th of February, 1945, warships approached the Japanese island of Iwo Juma. Abboard the ships was was an elite force of United States marines. Every man knew the importance of this mission. There were two air bases on Iwo Jima. It was just 750 miles from Tokyo.

It was a stepping stone. From Iwo Jima, our planes could directly bomb Tokyo or much of mainland Japan.

If they were able to take the island, the Americans would be one step closer to winning the Second World War in Pacific. The Americans had spent months planning this attack. They had begun with air rates to clear Japanese defenses on the slopes of Mount Suribashi. Now, they were ready to begin the amphibians assault.

There would be units landing on both major sides of the island. They would turn left and assault at the base of Mount Suribashi, and then other troops would begin to turn to the right and attempt to sweep east were towards the other end of the island.

The commanders had presumed that Japanese defenses would have been obliterated by the airstrikes. When the marines jumped from their ships and took their first steps on the black sand, though, they quickly saw this was not the case.

They drew immediate small arms fire, mortars, artillery from different positions. Literally the Japanese were throwing everything at them that they had.

Far from being destroyed, Japanese Japanese troops had dug in. 21,000 heavily armed men were hidden in bunkers, tunnels, and concrete pill boxes across Iwo Jima. The Marines were walking into a killing field. Moreover, they were doing so on literally shifting sands.

The sand on the beach of Iwo Jima is very loose. It's a black volcanic sand, so it's very difficult at any incline, maintain your balance. So you're slipping The sand is constantly giving away.

Wave after wave of marines landed on the beach and struggled to gain a foothold. The carefully planned mission was collapsing. The marines had no sense of where the fire was coming from.

Casuities were immediate. One of the worst fights of the entire Second World War in the Pacific.

The eighth wave of marines finally made it across the beach. They had with them a secret weapon. A group of men whose expertise could possibly turn the battle and the war. These men worked with codes, but they weren't code breakers. They were code talkers. They operated a system of communication that even the sharpest of enemies would struggle to crack.

They had to memorize all these alphabets and all the terms and be able to use them under fire and high pressure while they're trying to transmit and decipher the codes that they receive in as quick time as they can.

On the battlefields, code talkers relayed hundreds of messages, troop movements, casualty numbers, warnings of Japanese attacks, all with incredible speed and accuracy. These men were Navajo, Native Americans. They spoke a complex, unwritten language that bore little relation to most of those languages the enemies would have studied. Now, they were ready to use it in one of the bloodiest battles of the war. I'm Helena Boncarte, and for BBC Radio 4, this is History's Secret Heroes. True stories of Deception, Acts of resistance, and courage. From World War II. The Unbreakable Navajo Code.

. I explained in a traditional Navajo way that I am of white American settler descent through my mother, and I am born for my father's mothers and grandmothers. I am born for the towering house and black-streaked woods people clans of Denet, as we call ourselves, Navajo call ourselves.

Farina King is Associate Professor of Native American Studies at the University of Oklahoma. For her, the Navajo contribution to the Second World War is a deeply personal story.

My uncles, George Smith and Albert Smith, they were grandfathers to me. George was very quiet, very pleasant and kind. Albert was one who sat down with many people, including me, and wanted to be sure all his descendants, all his relatives knew Navajo culture, the Neh culture.

Albert and George Smith were born in the small town of Mariano Lake, New Mexico. Their childhood was spent outdoors herding sheep. Their families continued many many traditional practices of Navajo culture. Yet they and other native peoples grew up against a background of oppression that had been ongoing for centuries.

Natives had had a, it's hard to put it in enough emphasis in terms, a horrible situation for a long time.

William Meadows is a professor of Cultural Anthropology and Native American Studies at Missouri State University. Relations between European settlers and Native American communities had long been fraught.

Natives in general had went through decades, and in some cases, some groups, centuries of loss of land, confinement to reservation populations, food shortages, disease. By the time of World War I, Native American population, it was still at a very low point compared to what the traditional populations were in the past.

White European American settlers viewed that they had a right to the land, and it was a God-given destiny. I see it all as justifications to enable conquest, pushing Native Americans out of the way or killing them, humiliating them any way that they could. You find different colonizers saying things like, It's so expensive to kill Indians. Let's do something different. Let's change them into us.

From the mid-19th century, federal governments adopted policies of assimilation. Native children were often removed from their families, forcibly, if necessary, and put into boarding schools. These schools were often run by Christian missionaries with the aim of eliminating native languages and cultural practices. Away from their communities, Native children were punished harshly if they observed their own traditions. Emotional, physical, and sexual abuse of children in these schools was horrifyingly common. King's uncles, Albert and George Smith, were sent to a school in Fort Wingate.

You wake up, you march, you have a number, and the messages that were hammered into them was a belittling of the culture and language, and this sense that Navajo language was useless and you only need English to get by. The purpose, it was to civilize Indians.

George and Albert Smith were obliged to cut their long hair and wear European-style clothing Native religious practices, singing, and even games were banned, along with a Navajo language.

They had to stand for hours with their arms held up. If they were caught speaking Navajo at school. Their mouths washed out with soap, all kinds of torture for speaking Navajo. And my uncle, he had to hide to speak in Denebizad and talk to rocks and sticks in secret so that he would not get in trouble and be punished.

While the Smith brothers were carrying out these quiet acts of resistance at school, the United States was being dragged into the Second World War. On the seventh of December, 1941, the Imperial Japanese Navy launched a surprise attack on the American naval base of Pearl Harbor, on the island of Wauwahu, Hawaii. Over 300 Japanese aircraft reaped devastation on American airfields while battleships in the harbor were torpedoed, more than 2,400 American servicemen and women were killed. The United States swiftly declared war on Japan. Before long, millions of Americans will be mobilized in the nation's armed forces. In 1942, military recruiters arrived at Fort Wingate School. Boys aged 17 were invited to join up at the end of the school year. Many were inclined to do so.

A lot of natives, when they heard about Pearl Harbor, they felt that it was also an attack on them. Some people joined for economic reasons. There was little work at that time in the Depression.

George Smith was among those who decided to join the armed forces. He traveled to a registration center in Santa Fe to take physical tests and English examinations. His brother Albert, two years younger and only 15, was her age, but he listened in as George underwent training sessions and decided he would not be left behind.

George and Albert volunteered together and they wanted to fight. My uncle Albert, he lied about his age.

Years later, King When King asked her, Uncle Albert, why he volunteered.

He said, I wanted to protect my mother Earth. I wanted to protect my home, and that's my right. Whatever the past, whatever these issues are, I'm going to stand up and do that.

With the boys leaving for war, George and Albert Smith's family performed a traditional Navajo protection ceremony to keep them safe during battle. Despite the United States's long history of trying to stamp out native cultures, the American military had finally understood those cultures might have extraordinary value for them. 23 years earlier, World War I, the Western Front, France. American soldiers were fighting one of the fiercest battles of the First World War, yet they were getting nowhere. Every time they planned an operation, the Germans already seemed to be prepared for what they were going to do. They soon discovered why. German wire taps and telephone interceptions were compromising every communication operation. The Americans tried sending out runners to deliver messages, but the Germans intercepted them, too. A solution was stumbled upon by chance. In one American regiment, there was a company of Native American soldiers who spoke scores of different languages. The plan was for two of them who spoke the same language to be paired. One would report messages into a field telephone.

They will be given a message in English. They will turn around on the phone, put it into their native language to another speaker of their language. They will then verbally spit it back out in English to someone.

Native American languages, such as Navajo, are markedly different from European or Asian languages.

It's a complex language, so the syntax and the grammar is very different than Endo-European languages.

And crucially, very few have written forms.

So this is not the material that you could have found in a university library or publications in Paris or Berlin.

Outside Native American communities, hardly anyone spoke these languages, especially not in Europe. The Germans wouldn't have a clue what was being said. This was a far quicker way of encoding messages than any machine then in existence could achieve.

But it is a very small number of individuals, and it's only as As far as we know, it's only in a few units.

The Germans were stump.

It was portrayed as a slick trick. Look what we pulled on the Germans. Look what a novel idea this was that we use these native languages and they could never fathom them.

After the attack on Pearl Harbor, the American military attempted to develop new codes that would be harder for the enemy to break. The story of the Navajo code of the first war war had been forgotten. It took a civil engineer and veteran named Philip Johnson to reintroduce the idea. Johnson's parents were missionaries, and he'd grown up on a Navajo reservation. He was one of the very few non-native people who could understand some of the language. Johnston appealed to Marine Corps headquarters in San Diego, but they did not immediately leap on the idea. The Army, Navy, and Marine Corps had concerns about allowing Native Americans access to highly sensitive information.

There was a lot of skepticism and reticence. A couple of questions about, are they loyal? Can we trust them, et cetera? But also there was a certain level of distrust because, as some officers pointed out, the biggest problem is not whether they can speak their languages efficiently or not. It was that nobody in the military can monitor these messages.

While the army remained skeptical, the Marine Corps established a Navajo training program. Program. Among the recruits were Albert and George Smith.

My uncles were very clear that when they join the military, that's your family, those are your brothers, and you would die for them.

But Albert and George Smith had reason to wonder whether this solidarity went both ways. What would the European-American recruits make of the Native Americans?

The response of non-Indians to Indians in their unit was more of curiosity diversity, probably than anything else.

Sometimes they were taken for the enemy because of their resemblance to Asians or just the way that white Americans viewed them.

Marine training tested candidates to their limits with boot camps and forced marches. Many dropped out. The Smith brothers had grown up doing hard physical labor, ranching and herding sheep, so they were in excellent physical shape.

A lot of Navajos ran in the morning. Their families would get them up and they would run long distance before they went to school and things. So they were, on average, very, very physically fit.

On training marches, Marines were only allowed to carry one bottle of water. Navajo recruits would sometimes leave the route if they saw yucca plants, knowing they could extract water from them.

So at the end of this march, some of the Nandindians have already dropped out. They had to have trucks come get them and pick them up. Others are hurting badly from dehydration and everything. Well, when they get at the end of it, they ask them to open their canteens and pour it out and see what's left. And the Navajos basically have full canteens. They just pour them out and they're going, glug, glug, glug, glug, glug, and the non- Indian canteens are basically dry. And so they had a little bit of fun with their comrades here. I didn't tell them, but it gave them that image that these guys are superhuman.

It's not always an advantage if people think you have superpowers. Partly as a result of what were presumed to be their extraordinary physical capabilities, Native Americans were often given dangerous roles. They were selected to be scouts or to do reconnaissance work.

Consequently, using natives for a lot of these more dangerous positions, they do have a higher wound rate and killed in action rate than non-indians do.

Native American code talkers would have the most precarious and the most important position of all. Code talkers were recruited from several Native American nations, including the Mohawk, Comanchi, Seminole, and Mesquauki. In May 1942, 29 Navajo recruits arrived at Camp Pendleton on the Coast of California. They were asked to adapt their language to the brutal machinery of modern war.

It's a very complicated, intricate language. Even when you use one word like saying to go, there are so many different ways to say to go because it all depends on where you're going to, how you're going.

Albert and George later told their younger brother, Philip Lee Smith, Farina's father, about the work of the code talkers.

The thing that was important was telling the location of where the guns were, of what type of aircraft were in the air, what type of worry equipment and things that were used in the battle. You know, simple gunfire versus machine guns versus flame throwers.

The code talkers did not rely on the fairly safe assumption that few Japanese would speak Navajo. They created their own codes within the Navajo language, drawing on elements from the natural world. So to describe various types of airplanes, the code talkers use words for various birds. A fighter plane was a hummingbird, something slower moving, a type of owl.

Having a different bird for every type of aircraft that they would see.

In addition to birds, they used words for plants and animals native to New Mexico. Many of these would be unknown to Japanese code-breakers.

You don't see certain types of plants growing in the tropics that you see growing in the desert. You don't see the armadillo. You don't see the coyote or a certain type of mouse.

A destroyer became a shark. A submarine was an ironfish. A minesweeper was a beaver. The code talkers also encrypted regimen sizes and ranks of officers. Silver oakleaf signified a lieutenant colonel. Even coordinates could be described elliptically.

They would say. And what that meant was saying it's one degree's north, second degree's north, coming from the north.

The Navajo Code grew to encompass 400 terms with specific military applications. The final twist was the alphabet. Two or three words were used for each letter, all interchangeable. For instance, the letter I might be signified by ice, itch, or intestine. When these elements were combined, the results were formidably complex. One lieutenant set the recruits a They were asked to translate an important military message, transmit it, and then retranslate back to English. This task would normally take a soldier a few hours. The code talkers did it in two and a half minutes.

Something that my uncle always said to me is he said, We human beings have this great computer in our mind.

The irony was not lost on these men. Their language, which had been long suppressed by the United States government, was now a powerful tool in its service.

This is a common thread that I've heard Comanches and Navajos and other groups say over the years, Our language was our weapon.

New Navajo recruits joined and learned the code. They also learned how to transmit and receive messages under fire. If a recruit could successfully decode a three-line message in under 20 seconds, he was considered ready for the front. As the war in the Pacific raged on, When he was born, nearly 400 Navajo code talkers were deployed across dozens of battles. Albert was stationed in the Marshall Islands, George trained in Hawaii and fought in the battles of Saipan and Okinawa. Code talkers carried rifles and radio sets as largest suitcases. They acted in pairs, one on the battlefield, sending the messages in Navajo code, the other receiving and translating them into English. They gave the Americans a remarkable advantage advantage. Every Japanese code had been broken, but not a single Navajo message was decoded by the enemy.

So the code talkers in the Marine Corps became very, very respected. Other soldiers would offer to carry their equipment sometimes or help them out a little bit because they knew they could get artillery in 2-3 minutes. If they got into hot stuff, they were really their lifeline.

Late in 1944, though, the Japanese made a breakthrough. After the fall of the Philippines, the Japanese army captured a Navajo soldier, Joe Kyumia. He was being held in a prison camp in Nagasaki, where he'd already endured two years of hard labor.

They pulled him out of that camp and brought him to a room and was having him listen to recordings of what was the Navajo Code Talkers using their code.

If he didn't give them the right answer, Kyumia knew he would be tortured.

He was a very fluent speaker of Navajo, but even then, he could not understand what they were saying. He could not break the code because he wasn't trained in it.

Kyumia was brutally tortured for failing to crack the code. He survived both the torture and his subsequent imprisonment at Nagasaki and was released at the end of the war to return to the United States. Beyond the damage inflicted on Kyumia personally, though, his capture could have threatened the whole American war effort in the Pacific. Had the co-talkers not created such an ingenious, encrypted version of Navajo, the Japanese might well have deciphered everything they sent from then on. After they had identified Kyumia, the Japanese knew the Navajo language was being used against them. But even a native Navajo speaker could not decipher it for them unless he'd been trained as a code talker. On the 19th of February, 1945, the mist was clearing spring, and the island of Yauwa-jima came into view. Albert Smith was aboard the ship. He took some corn pollen from a pouch and prayed. By the time his ship approached the beach, the catastrophe was unfolding. One co-talker had already been killed among hundreds of other marines. Now it was Smith's turn to land.

The island itself had miles of underground tunnels. It had what are called spider holes where a man can pop up out of a single hole, fire, throw a grenade, et cetera, and then pop back down and disappear. Every single spot had something coming out of it. Machine gun bunkers. There was no safe area.

The Marines advanced in small groups. Smith moved with his unit. The Japanese understood very well the importance of communications on the battlefield, and Smith knew they would target him and his radio. He ducked down in shell craters. Under intense fire, he radioed information back to the ships.

So it can be ammunition resupply. It can be movement of troops to strategic places, medical supplies, evacuation of wounded. The first 48 hours on Iwo Jima was done pretty much exclusively in Navajo. And the reason being is that the Japanese could not intercept it. They could hear it, but they couldn't understand it.

Nearly four weeks later, at 6:00 PM on the 16th of March, American forces finally declared that they had secured Iwo Jima. The battle had raged for 25 days. Victory came at a terrible cost. Over 6,000 Americans were killed, more than 19,000 wounded. But the United States had won the battle, and they'd done it with the help of the Navajo Code.

That's what allowed us to get a tow the foothold on the island.

The foothold established at Iwo Jima allowed the Americans to attack Okinawa. Two atomic bombs were detonated, first at Hiroshima and then days later at Nagasaki. Japan surrender. The war in the Pacific finally came to an end. For many years after the war, the work of the Code Talkers remained confidential. Albert and George Smith could not tell their families what they done during the war. Albert once said that he was told by his elders to leave his war stories behind, leave it where it happened. When at last the story of the Code Talkers was celebrated, many of the men involved were elderly. In 2001, at a ceremony in the capital in Washington, DC, the Smith Brothers received the Congressional Medal of Honor. The emotion was overwhelming.

I saw how proud my uncles were to be celebrated, finally, to be recognized, to share their stories of struggles and what they went through and how inspirational that is.

These men, most of them came out of government boarding schools that were attempting to suppress the language. And so there is an aspect of survival there. And also, I think it speaks to the resilience of these young men.

The Navajo Code is the only unbreakable military code in military history. Let that sit in with you. Our language changed the very outcomes of World War II.

Next time on History's Secret Heroes, after contracting Hansen's disease, then known as leprosy, Josefina Guerrera makes a remarkable decision. She becomes a spy for the resistance in Manila.

She often did things like wearing a veil, dressing in black. She would announce that she was a leper by saying, Unclean, unclean.

They thought, Well, this sick person is not going to be a part of the resistance.

The maid of Manila. Devon, the summer of '89. I think the same night he fell in love twice, once with Clotted Cream and maybe once with me. The beginning of an epic love story that begins with a first kiss on a pier. I still remember she had a black dress and she had a smile. And ends And, well, I'm not going to tell you that, am I? I'm Matthew Side, and this Nostalgia Drench story is part of the latest season of my BBC Radio 4 podcast, Sideways. Six new stories which explore the ideas that shape our lives. Join me, Matthew Side, for Sideways on BBC Sounds.

Tesco Club Card gives you the power to lower prices so you can taste the start of summer. With our Bordbeia quality-assured Tesco Finest Irish Tea Bone Steak, now half price. Plus our wide range of Tesco ice creams are now two for four euro. And get three for four euro from the selected Cadbury and Sour Patch Kids ranges. Lower the cost of your shop with your Tesco Club card or app. The power to lower prices. Save time, shop online or click and collect. Tesco. Every little helps. Products subject to availability, prices vary in express stores.

At Holland & Barrett, we believe it's time to change the way we think about our hormones. We've heard for too long, you're hormonal, but that's normal. Let's learn how to work together with our hormones so we're united in our quiet days, high days, what's happening to me days, the wonders of life days, because when we understand our rhythm, we can own every day of the month. Find personalized solutions to support your hormone health now on 3 for 2 at Holland & Barrett. Offer ends 14th of May, subject to availability.