The Romans say that the Celts lost their tempers and quarrelled often - but we don't know that. After all, they couldn't have been fighting all the time - they'd be too tired to do any farming! The farmers had to be ready to fight whenever the head of the tribe called on them.
The Celts often fought naked - and it's believed that women would fight as well. Their main weapons were the sword and spear, like the iron sword in the picture above, and they sometimes fought in horse-drawn war chariots.
The power of the Romans
Even though the Celts were proud, brave and skilled fighters, they were rather undisciplined. They really had little chance against the Romans' order and power. And, of course, in the end they were defeated by the Romans.
This wooden sword was discovered in a pond at the Breiddin hillfort site, near Welshpool in mid Wales - the wet conditions had preservde it over the years. The sword could have been a toy, a weaving tool, or a gift to the gods.
Tacitus said that Celtic women were as large and frightening as the men. If this is true, no wonder they took part in the fighting too! Bouddicca is a famous female fighter. Chief of the Inceni tribe, she is described as having thick red hair down to her knees - a bit like Fearless Ffion in our Games & Stories, perhaps.
She wore a colourful tunic, a gold torc around her neck and a cape of thick tweed pinned with a brooch. When she went to fight, she held a spear in her hand. She didn't like the Romans and revolted against them.