14 October 2025 The Future is the Product of the Past

Artifacts found in Japan could be prototypes of ninja weapons

Artifacts discovered in the ruins of structures associated with warlord Toyotomi Hideyoshi’s 1590 Siege of Odawara may be prototypes of ninja weapons.

The flat stones and clay balls may well have been the forerunners of “shuriken” throwing stars and “makibishi” caltrops that later made up ninja arsenals, Akihiro Iwata, archaeologist and curator at the Saitama Prefectural Ranzan History Museum, told Asahi.

The term shuriken actually covers a multitude of throwing weapons employed by the Ninja. The skilled ninja would use a Shuriken as a distraction or secondary attack rather than a means to kill or disable their foe.

The caltrop is referred to as Makibishi in Japanese. The weapon (igadama) is a sharp spiked item that was used to slow down pursuers and defend samurai fortresses in medieval Japan. Makibishi could also be thrown like a shuriken.

After re-examining artifacts from the late Warring States era (late 15th to late 16th centuries) unearthed at archaeological sites in Saitama and Hachioji in western Tokyo, Iwata came to this conclusion.



📣 Our WhatsApp channel is now LIVE! Stay up-to-date with the latest news and updates, just click here to follow us on WhatsApp and never miss a thing!!



Clay caltrops unearthed at the ruins of Hachioji Castle. They are kept by the Hachioji City Historical Museum. Photo: Saitama Prefectural Ranzan Historical Museum
Clay caltrops unearthed at the ruins of Hachioji Castle. They are kept by the Hachioji City Historical Museum. Photo: Saitama Prefectural Ranzan Historical Museum

Between the 1990s and 2000s, flat throwing stones with sharpened corners were discovered at the ruins of Iwatsuki Castle and the Owada jin’ya administrative headquarters in Saitama, both in Saitama.

A hexagonal stone from the Iwatsuki Castle ruins measured 4.8 centimeters in diameter and 1 cm thick, while 17 stones from the Owada jinya measured 8 to 14 cm in diameter and 1.5 to 3 cm thick.

The Siege of Odawara forced the rival Hojo clan to hole up in Iwatsuki Castle before it fell. The Owada jinya, located about 6.5 kilometers away, may have been its branch castle.

Edo period shuriken in Odawara Castle Museum, Japan. Photo: Wikipedia
Edo period shuriken in Odawara Castle Museum, Japan. Photo: Wikipedia

Four unglazed clay balls were among items excavated at the ruins of Hachioji Castle around 1960.

Each ball, measuring approximately 1 to 3 cm in diameter, has four spike-like projections so that one of them points upward, apparently to slow the advance of enemy forces.

Hachioji Castle also fell during the Siege of Odawara.

“It is possible that the Hojo clan made these getaway weapons after realizing it faced Hideyoshi’s overwhelming force,” Iwata said.

Japanese "makibishi" iron spikes, a type of caltrop
Japanese “makibishi” iron spikes, a type of caltrop. Photo: Wikipedia

He added that the forms of these primitive tools suggest that they may have been the prototypes of shuriken and other weapons used by the feudal-era undercover agents.

Yuji Yamada, a ninja expert and professor at Mie University’s Faculty of Humanities, described the artifacts as “groundbreaking discoveries.”

“Flat throwing stones could have developed into shuriken in later years,” he said. “I had never seen clay caltrops before.”

Cover Photo: Saitama Prefectural Ranzan Historical Museum

Related Articles

A Mysterious 1,800-year-old Roman Statue Unearthed During Car Park Construction Work in UK

13 March 2024

13 March 2024

A 1,800-year-old Roman marble statue of a woman’s head was discovered during construction in the parking lot of Burghley House...

Archaeologists discover bones of a woman who lived 14,000 years ago at a site in The Iberian Peninsula

13 August 2021

13 August 2021

Archaeologists have discovered the bones of a lady who lived 14,000 years ago, the earliest traces of a modern burial...

A Nymphaeum was discovered in the ancient Thracian city of Perperikon

18 August 2023

18 August 2023

New researchs uncovered a huge monumental sanctuary of water (Nymphaeum) above the reservoir in the southern quarter of Perperikon. Professor...

Incredible Mayan Inventions and Achievements

31 July 2022

31 July 2022

The Mayans excelled at agriculture, pottery, writing, calendars, and arithmetic, leaving an incredible quantity of spectacular architecture and symbolic artwork...

A Rare Find That Stuns Archaeologists: Ancient 3,500-Year-Old Dagger Found in Germany’s Heartland

22 August 2025

22 August 2025

A simple family walk near the village of Gudersleben in Nordhausen County, in Thuringia, central Germany, has turned into a...

A pendant with a figure of St. Nicholas found in the Ancient Church Hidden in Turkish Lake

7 October 2022

7 October 2022

Underwater archaeological excavations and research, which were started 8 years ago in the basilica located 20 meters off the lake...

Archaeologists Uncovered a Terracotta Commander and Warriors at the Mausoleum of China’s First Emperor

12 January 2025

12 January 2025

Archaeologists have unearthed a rare 2,000-year-old statue depicting a high-ranking military commander at the famous Terracotta Army site in China:...

A rare statue of K’awiil, Mayan god of Lighting have uncovered in Mexico

1 May 2023

1 May 2023

In southeastern Mexico, archaeologists uncovered a rare sculpture of a powerful Mayan god near the path of a large-scale rail...

Unique and very well-preserved prehistoric engravings found in southwestern Catalonia

23 March 2023

23 March 2023

Significant prehistoric rock art has been discovered in La Febro, in southwestern Catalonia. The team that discovered the art inside...

9 Relics of Neanderthal Found in The Guattari Cave

8 May 2021

8 May 2021

Archaeologists in Italy have discovered the remains of nine Neanderthals who were reportedly killed and mauled by hyenas in their...

2,300-year-old Punic tomb complex found during works on car park for staff

26 October 2024

26 October 2024

A 2,300-year-old Punic tomb was discovered during work in a car park near Mater Dei Hospital in Msida, Malta. The...

The first ivory work of art recovered from the World Heritage cave Hohle Fels was believed to be a horse – until archaeologists made a new discovery-

30 July 2023

30 July 2023

For more than 20 years, the first ivory work of art recovered from the World Heritage cave Hohle Fels was...

Archaeologists Unearth Carolingian Silver Treasure Hoard

6 May 2021

6 May 2021

A silver treasure hoard from the 9th century AD has been discovered in Poland‘s Osa and Drwęca basin. The hoard...

Human Activity on Curaçao Began Centuries Earlier Than Previously Believed

28 March 2024

28 March 2024

New research co-led by Simon Fraser University and the National Archaeological Anthropological Memory Management (NAAM Foundation) in Curaçao extends the...

Archaeologists uncovered a 3,500-year-old Egyptian Royal Retreat in the Sinai Desert

5 May 2024

5 May 2024

An Egyptian mission uncovered the ruins of a 3,500-year-old “royal fortified rest area” at the Tel Habwa archaeological site in...