27 May 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.

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

Homo Bodoensis may be the ancestor of modern humans

28 October 2021

28 October 2021

Although modern humans are the only surviving human lineages, their kinship with other human species that roamed the world is...

1900 years old a Customs Inscription from the Lycian civilization reveals Anatolia’s strategic importance in maritime trade

16 September 2023

16 September 2023

A Customs Inscription from the Lycian civilization, located in Andriake port in the southern province of Antalya’s Demre district, tells...

Works on Brussels metro line uncovered remains of the second city wall

18 April 2023

18 April 2023

Construction work on the new metro line 3 in Brussels, the Belgian capital, has revealed part of the second rampart...

New fibula types discovered at prehistoric Kopilo graves in Bosnia

26 August 2022

26 August 2022

An archaeological dig at Kopilo, a hill settlement founded around 1300 BC about 70 miles west of Sarajevo, has discovered...

The ruins found in Nara could be the Imperial House of Female Emperor Koken

1 July 2021

1 July 2021

Archaeologists unearthed one of the largest building remains ever found at the former site of the Heijokyu palace in the...

5000-year-old jewelry factory found in Rakhi Garhi in India’s Indus Valley region

9 May 2022

9 May 2022

The Archaeological Survey of India (ASI) has made an important discovery by finding the remains of a 5000-year-old jewelry factory...

Ancient Synagogue found in Turkey’s popular tourist center Side

27 December 2021

27 December 2021

A 7th-century ancient synagogue has been found in Side, a resort town on Turkey’s Mediterranean coast. The synagogue found was...

First in Anatolian Archaeology, a 2,600-year-old Sacred Room and Stone Symbolizing the Goddess Kubaba Discovered at Oluz Höyük

29 November 2024

29 November 2024

Archaeologists have discovered a sacred room and stone from the Phrygian period, dating back 2,600 years, during excavations at the...

Researchers may have found the wreck of British explorer James Cook’s Endeavour

3 February 2022

3 February 2022

The wreck of Captain James Cook’s famed vessel the Endeavour has been found off the coast of the U.S. state...

The 1,800-year-old ‘Iron Legion’ Roman Legionary Base uncovered at the foot of Tel Megiddo

14 February 2024

14 February 2024

The Israel Antiquities Authority (IAA) announced that a recent excavation at the foot of Tel Megiddo, near the ancient village...

Assos Excavations Reveal 2,200-Year-Old Mosaic and Monumental Tomb

10 March 2025

10 March 2025

Archaeological excavations in the ancient city of Assos, situated in Behramkale village in Türkiye’s Çanakkale province in the northwestern part...

A Roman sarcophagus bearing the title of “Emperor’s Protector” was found for the first time in Anatolia

29 April 2022

29 April 2022

A sarcophagus carrying the title of “Emperor’s protector” was discovered in the province of Kocaeli in western Turkey. With the...

Unusual construction material may be linked to the Tower of Babel

5 November 2021

5 November 2021

Archaeologists have recently discovered bitumen and mortar plastered onto a brick dating back to the Babylonian King Nebuchadnezzar II. This...

An 8500-year-old wooden ladder remain was discovered at Çatalhöyük

12 April 2022

12 April 2022

Remains of the wooden ladder were discovered for the first time in Çatalhöyük, one of the best-preserved Neolithic settlements in...

Largest-Known Flower Preserved in Amber Is Nearly 40 Million Years Old

20 January 2023

20 January 2023

The largest-known fossilized flower encased in amber, dating back nearly 40 million years, was again discovered in the Baltic region...