The Celtiberians were a group of people who were Celts or had Celtic influences, living in the central-northeastern part of the Iberian Peninsula during the last few centuries before the Common Era. Ancient writers, such as Strabo, clearly described them as Celts. These tribes spoke the Celtiberian language, which they wrote using a version of the Iberian alphabet called the Celtiberian script. Many inscriptions found by scholars, some of which are long, have helped experts classify the Celtiberian language as a Celtic language. It belongs to the group of Hispano-Celtic (also called Iberian Celtic) languages spoken in Iberia before and during the early Roman period. Archaeological findings show similarities between the Celtiberians and Celts in Central Europe, but also differences compared to the Hallstatt and La Tène cultures.

There is no complete agreement among ancient writers or modern scholars about the exact definition of the Celtiberians. The Ebro River clearly separated Celtiberian areas from regions where people did not speak Indo-European languages. In other directions, the boundaries are less clear. Most scholars include tribes such as the Arevaci, Pellendones, Belli, Titti, and Lusones as Celtiberian groups. Some sources also mention the Berones, Vaccaei, Carpetani, Olcades, or Lobetani as possibly Celtiberian.

In 195 BC, part of Celtiberia was taken over by the Romans. By 72 BC, the entire region became part of the Roman province of Hispania Citerior. The Celtiberians who were conquered resisted the Romans for many years, leading uprisings between 195–193 BC, 181–179 BC, 153–151 BC, and 143–133 BC. In 105 BC, Celtiberian warriors helped drive the Germanic Cimbri out of Spain during the Cimbrian War (113–101 BC). They also played a key role in the Sertorian War (80–72 BC).

Etymology

The term Celtiberi is mentioned by ancient writers such as Diodorus Siculus, Appian, and Martial. These writers noted that Celts and Iberians married each other after a long period of fighting. However, Barry Cunliffe said this idea sounds like a guess. Strabo believed the Celtiberians were part of the larger group called the Celti. Pliny the Elder thought the original home of the Celts in Iberia was the area of the Celtici in the southwest. He based this on similar religious practices, languages, and city names.

History

Strabo mentions Ephorus’s idea that Celts lived in the Iberian Peninsula as far as Cádiz.

Celtic people may have arrived in Iberia as early as the 6th century BC. At this time, castros—settlements with stone walls and ditches—showed a more permanent way of life. Archaeologists Martín Almagro Gorbea and Alberto José Lorrio Alvarado note that the tools made of iron and the family structures of the developed Celtiberian culture came from the earlier, simpler castro culture, which they call "proto-Celtic."

Archaeological discoveries show that this culture was the same as what Classical writers described from the late 3rd century BC onward. However, the people of Celtiberia were not a single group. Instead, many different tribes and nations lived in the region, centered around fortified towns called oppida. These groups had mixed Celtic and Iberian backgrounds and showed different levels of connection with local cultures.

The main area of Celtiberian culture was the northern part of the central meseta, in the upper valleys of the Tagus and Douro rivers east of the Ebro river, in modern-day provinces of Soria, Guadalajara, Zaragoza, and Teruel. When Greek and Roman writers described them, the Celtiberians were ruled by a military class that passed power from one generation to the next. The Arevaci tribe was the most powerful, controlling strongholds like Okilis (Medinaceli) and leading long resistance against Rome. Other groups included the Belli and Titti in the Jalón valley and the Lusones to the east.

Excavations at Celtiberian strongholds like Kontebakom-Bel Botorrita, Sekaisa Segeda, and Termantia, along with grave goods found in cemeteries, show changes in burial practices. Aristocratic tombs from the 6th to 5th centuries BC were replaced by warrior tombs. By the 3rd century BC, weapons were no longer placed in graves, possibly because they were needed by living warriors or because society became more urbanized. Many late Celtiberian towns are still occupied today, making it hard for archaeologists to study them.

Metal items are common in Celtiberian finds, likely because metal lasts a long time. These items often show war-related uses, such as horse gear and weapons. The two-edged sword used by the Romans was already in use among the Celtiberians. The Latin word for a thrown spear, lancea, came from the Iberian region, as noted by Varro. Over time, Celtiberian culture became more influenced by Rome.

By the 3rd century BC, the clan was replaced by the oppidum, a fortified city with its own territory that included smaller castros. These cities, called civitates by Roman writers, could form alliances and even mint coins. However, the old clan system remained in the way armies were organized, leading to problems with strategy and control.

The Celtiberians were the most powerful group in Iberia when Mediterranean powers like Carthage and Rome began conquering the region. In 220 BC, a Punic army preparing to cross the Tagus River was attacked by a coalition of the Vaccei, Carpetani, and Olcades. During the Second Punic War, the Celtiberians often fought for Carthage against Rome, including joining Hannibal’s forces in the Alps. Later, under Scipio Africanus, the Romans won over many Celtiberian tribes, using them to fight Carthaginian forces in Spain. After the war, Rome took control of Spain, and some Celtiberians resisted the new power. Tiberius Sempronius Gracchus led campaigns from 182 to 179 BC, claiming to destroy over 300 Celtiberian settlements.

In 155 BC, the Lusitani attacked Roman forces in Hispania Ulterior (Farther Spain), leading the town of Segeda in Hispania Citerior (Nearer Spain) to rebel. Segeda refused to pay tribute to Rome and formed alliances with nearby towns, building a wall for defense. In 153 BC, Quintus Fulvius Nobilior led a Roman army of nearly 30,000 men against the Celtiberians but was ambushed, losing 6,000 soldiers. A siege of Numantia, where the Segedans had taken refuge, failed when Roman elephants turned on the soldiers. Nobilior’s campaign ended with over 10,000 Roman deaths. In 137 BC, the Celtiberians defeated a 20,000-man Roman army led by Gaius Hostilius Mancinus. In 134 BC, Scipio Aemilianus took command of the Roman forces in Spain and laid siege to Numantia.

The Romans destroyed nearby fields and built a ditch and wall around Numantia, with towers and weapons like catapults and ballistae. Logs with knives and spearheads were placed in the river to block enemy movement. Allied tribes, including Jugurtha (who later rebelled against Rome), sent reinforcements. The Roman army numbered 60,000 men, arranged in seven camps around Numantia. The Numantians, determined to fight, made several failed attempts to break out of the siege. Eventually, starving and desperate, they sent envoys to Scipio, asking for mercy. Scipio refused, demanding complete surrender. The Numantians killed their own ambassadors instead.

After eight months of starvation, the Numantians resorted to cannibalism and were forced to surrender

Genetics

In a study published in the journal Science in March 2019, scientists examined three Celtiberians who were buried in La Hoya, Alava (part of the Beron territory) between 400 BC and 195 BC. These individuals had a high amount of genetic traits linked to people from north-central Europe, which was different from other non-Celtic groups in Iberia. One of the males studied was found to carry a specific type of genetic marker known as the paternal haplogroup I2a1a1a.