In the autumn of 1945, occupying Tokyo, American debriefers from the United States Strategic Bombing Survey asked Lieutenant General Seizo Arisu, the man who had spent the last three years of the war running Japanese Army intelligence, what he had managed to read. His answer was honest. The Army codes, yes. The Army Air Corps codes, yes.
The Marine Corps tactical traffic in the Pacific? No. They had never broken it. By the end of the war, they had not even been able to identify what language it was in.
Imperial Japan in 1942 fielded one of the most accomplished military intelligence services on Earth. Japanese cryptanalysts had chewed through American Army field ciphers before Pearl Harbor, reconstructed American merchant shipping schedules months in advance, and pieced together fragments of State Department diplomatic traffic in the late 1930s. By every measure their profession recognized, they should have broken anything the Marine Corps put on the airwaves. None of their methods could read what waited on the Marine command frequencies, and the reason stretched back eighty years.
In August of 1863, Brigadier General James Henry Carleton, commander of the Department of New Mexico, ordered Colonel Christopher Carson and the 1st New Mexico Volunteer Cavalry to ride into the Navajo homelands. Carson was not to engage in pitched battle. He was to destroy what kept the Navajo people alive. Through the late summer, fall, and bitter winter that followed, his troopers moved through the land the Navajo called Dinétah, burning cornfields, slaughtering sheep, and cutting down the peach orchards of Canyon de Chelly that had grown there for generations.
By January of 1864, the Navajo were starved into surrender. What followed is remembered by the Navajo as Hwééldi, the place of suffering. White historians call it the Long Walk. More than 10,000 Navajo men, women, and children were forced to march on foot, sometimes 450 miles, to a barren forty-square-mile reservation at Bosque Redondo on the Pecos River.
Hundreds died on the trail. Pregnant women who could not keep up were shot, stragglers were shot, and children were taken by slave traders. The army officers who had ridden the country had objected to the site; the soil could not feed a thousand people, much less ten thousand. Crops failed every year, the water was bad, and disease moved through the camps.
Roughly one in three interned at Hwééldi died there before the Treaty of Bosque Redondo released the survivors on June 1st, 1868. Walking home, the survivors carried a language. The treaty returned a fraction of their homeland, but the country was wrecked: fields ash, orchards cut down, herds destroyed. They rebuilt anyway.
The grandparents and great-grandparents of the men who would one day build a military code were the generation that carried that language home from Hwééldi. The federal government, having finished one military project, began another. Through the late 19th and early 20th centuries, the Bureau of Indian Affairs ran boarding schools whose explicit policy was the removal of Navajo children and the eradication of the Navajo tongue. Children were taken at six or seven, their hair cut, their clothes taken, given new English names, often the names of dead presidents, and warned not to use the language they spoke at home.
When they slipped, they were beaten. Some had their mouths washed with lye soap, some had their tongues struck with rulers. The model was Captain Richard Pratt, founder of the Carlisle Indian Industrial School, whose slogan was: Kill the Indian in him and save the man. The language survived anyway.
It survived because grandmothers spoke it to babies in cradleboards out of earshot of the schools, in whispered nightly prayers of children beaten for it that morning, and because Navajo families taught their children to live a double life: an English life for the schools and trading posts, and a Navajo life for home. A boy named Chester Nez, born in Chichiltah, New Mexico in 1921, was sent to a Bureau of Indian Affairs boarding school at Tohatchi at age eight, speaking no English. He was given the name Chester after the late President Chester Arthur and warned not to speak Navajo. When he forgot, he was punished.
Decades later he would describe the system as one designed to remove him from himself. By the time Japan struck Pearl Harbor, perhaps thirty non-Navajos in the entire world spoke the language fluently. The Navajo themselves numbered around fifty thousand, second-class citizens in the country whose fight they were about to volunteer to join. New Mexico and Arizona would not let them vote.
The Marine Corps had a problem. Everything the Marines said by radio, the Japanese were reading. American operational ciphers in 1941 and 1942 were a patchwork of older systems and slow mechanical devices. A typical tactical message had to be written in English, fed through a coding machine word by word, transmitted, received, and run back through a machine, a cycle that could take half an hour.
In a battle measured in minutes, that was eternity. Worse, Japanese signals intelligence, built through the late 1930s into one of the most experienced cryptanalytic services in Asia, was reading low-level Marine field traffic almost in real time. On Guadalcanal in August of 1942, the men in foxholes around Henderson Field had no secure way to call for artillery or coordinate movement. The official Imperial Army assessment of the Marines, recovered after the war, called them brave but predictable, and their codes a curtain of paper.
The man who changed that was a 49-year-old civil engineer for the Los Angeles Water Department named Philip Johnston. Johnston had grown up speaking Navajo with Navajo children on the reservation and had served in France in the First World War, where he heard of a small experiment with Choctaw soldiers who baffled the Germans with their native language. He filed the memory away. Pearl Harbor brought it back.
Johnston knew Navajo was almost the only language on earth with everything the military needed and nothing the enemy could exploit. It had no written form, no published grammar, and tones that could shift the meaning of a word entirely. No German university and no Japanese institute had ever studied it. In late February of 1942, with four Navajo friends recruited from Los Angeles shipyards, he gave a demonstration at Camp Elliott before Major General Clayton Vogel.
Vogel handed the speakers a typical six-line English combat message. They translated it, transmitted it across the room in Navajo, received it on a second radio, and translated it back. Total elapsed time: about twenty seconds. The mechanical machines needed thirty minutes.
Vogel recommended the Marines recruit two hundred Navajos at once. The recommendation was reduced to a thirty-man pilot project. The men who actually built the code were not Johnston. They were twenty-nine young Navajo Marines who had not yet finished boot camp.
Recruiters set up at trading posts and high schools and the Public Health Service office at Fort Defiance in April of 1942. The assignment was described only as special duty. Two hundred fifty men reported; twenty-nine were chosen. They were sworn in at Fort Wingate on May 4th, 1942, an old army fort converted into a boarding school.
The irony was not lost on them. They went through boot camp as Platoon 382, the first all-Navajo platoon in Marine Corps history, and graduated on June 27th. Then they were walked into a locked room at Camp Elliott, told to develop a military code in their own language, and the door was locked behind them. They had not a single trained cryptographer among them.
The code they built had two layers. The first was a phonetic alphabet in which each English letter was assigned several Navajo words, so that the letter A could be the word for ant, apple, or axe, meaning even if a listener figured out one substitution, the letter would be encoded differently next time. The second layer was a vocabulary for military terms that did not exist in Navajo. Submarine became iron fish.
Tank became tortoise. Dive bomber became chicken hawk. Battleship became whale. America became our mother.
Each substitution was agreed on and memorized by all twenty-nine men, because the code would never be written down. It existed only in their heads. When tested, they could encrypt and transmit a three-line battlefield message in roughly twenty seconds. Marine cryptographers were given recordings and could not even transcribe the sounds, much less break them.
The first group of code talkers reached Guadalcanal on September 18th, 1942. Chester Nez arrived in early November and sent his first combat transmission a few days later: a request for an artillery strike on a Japanese machine gun nest. The rounds hit exactly where he directed. By Tarawa in November of 1943, code talkers were attached to every Marine division.
By Saipan, commanders were so dependent on them that requests outpaced the training of replacements. The men worked in pairs, one on the radio, one relaying, never writing anything down. On Iwo Jima in February of 1945, the battle became a thirty-six-day meat grinder that took roughly seven thousand Marine lives and wounded twenty thousand more. Major Howard Connor, the Fifth Marine Division Signal Officer, had six code talkers under his command.
In the first forty-eight hours they transmitted more than eight hundred messages without a single error. Connor would later say that without the Navajos, the Marines would never have taken Iwo Jima. When the flag went up on Mount Suribachi on February 23rd, the message announcing it went out in Navajo, spelled letter by letter using the phonetic alphabet. The Japanese knew what they were facing.
In 1943 and 1944 they captured a Navajo soldier named Joe Kieyoomia in the Philippines. He was not a code talker; he had never been trained in the code. His captors brought him recordings of intercepted transmissions and ordered him to translate. He understood the words were Navajo.
He could pick out nouns, sheep, water, beaver, eagle. None of it meant anything as a message. They did not believe him. He was forced to stand naked in the snow until his feet froze, and beaten so badly he lost use of a leg until after the war.
He survived the atomic bomb at Nagasaki. After the war he said that even if he had known the code, he would never have given it up. In the post-surrender debriefings, General Arisu admitted his service had never broken the Marine traffic. The Tokyo newspaper Yukan Fuji observed that if Japanese intelligence had decoded the Navajo messages, the outcome of Saipan and Iwo Jima might have been different, and the history of the Pacific War might have turned out completely differently.
The program was classified after the war, and the men were ordered not to speak of it. The order held until 1968, when the Department of Defense quietly declassified it. Many of the men were dead by then. Recognition came in pieces: President Reagan declared August 14th Navajo Code Talkers Day in 1982, and in July of 2001, the original twenty-nine were awarded the Congressional Gold Medal in the Capitol Rotunda.
Chester Nez, the last of them, died on June 4th, 2014, at ninety-three. The Navajo Nation lowered its flags.
