Japan’s ancient samurai festival shifts to cooler dates as climate change threatens tradition

Japan’s Soma Nomaoi — a thousand-year-old festival where riders in full samurai armor race on horseback — has outlasted wars, earthquakes, and even the Fukushima nuclear disaster. Now it is confronting a threat that no amount of tradition could have prepared it for: climate change.

For centuries, the event took place at the peak of Japan’s brutal summer heat. But by 2024, temperatures had become so extreme that riders and spectators were collapsing, and horses were dying from heatstroke. Organizers made a historic call: move the festival to late May, when temperatures are significantly cooler.

Mitsukiyo Monma, a 69-year-old who has taken part for 54 years, told AFP the change was transformative. "You have to wear a kimono under the armor — it's not like going out in just a T‑shirt in the summer," he said. He recalled needing medical attention one year when the mercury neared 40°C (104°F). "Your clothes would be so soaked that you could wring out the sweat. When the festival moved to May, it was the first time I could drink hot coffee before going out."

Scientists say climate change is driving more frequent and severe extreme weather events worldwide. Japan is no exception. Last year, the country recorded its hottest summer since records began in 1898. Temperatures above 40°C have become so common that Japan’s weather agency recently created a new official designation for them, calling them "cruelly hot" days.

Such conditions are hardly ideal for a festival where participants compete on horseback while wearing samurai armor weighing around 25 kilograms (55 pounds). The main event features races around a flat oval track, with riders carrying giant flags on their backs. Hundreds then gather in a grassy field to grab colored flags that drift down after being fired into the air. On the final day, participants attempt to catch wild horses with their bare hands and offer them to the gods.

"I feel like I’ve truly become a samurai," Monma said. "I feel more courageous, and on the day itself, my whole body and mind tighten."

The Soma Nomaoi takes place around Minamisoma, about 300 kilometers (190 miles) north of Tokyo. It began roughly 1,000 years ago, and records suggest it has been held uninterrupted for at least the last 400 years. The festival continued even after the devastating 2011 earthquake and tsunami that left more than 18,000 people dead or missing and triggered the Fukushima nuclear meltdown.

Fumihiko Futakami, director of the Minamisoma City Museum, recalled how the festival was a comfort when he was evacuated to Tokyo after the disaster. "Even for people who have left here and now live elsewhere, when they think of their hometown, they think of mounted warriors," he said. "It's the identity of our town."

The festival’s samurai roots meant only warriors could participate until the feudal system was abolished in the late 19th century. Women were admitted after World War II, and this year Monma fulfilled a lifelong dream when his two granddaughters joined him under cloudy skies with temperatures hovering around a pleasant 18°C (64°F). There was little chance of a repeat of the 2023 event, when more than 100 horses and dozens of people needed treatment for heatstroke, and two horses died.

"There isn't much shade anywhere, so I think this is the most comfortable temperature for everyone," said Haruto Inoue, a 25‑year‑old visiting from nearby Tochigi to watch the festival for the first time. "They look so cool in their samurai gear, racing through the mud and giving it everything they've got."

Despite the successful shift, the festival faces an uncertain future. Anyone can participate, but owning or hiring a horse is expensive, and the number of participants has been steadily declining. Japan’s aging population is a major factor. Monma worries the festival might not survive another 100 years unless organizers find solutions. Museum director Futakami believes moving away from the punishing summer heat is a good start. "The horses are livelier and the participants aren't so exhausted that they can barely move the next day," he said. "I think most people would say it's been a good thing."

— amk/aph/cms/hol