The Proto-Celts had developed a culture of cremation of the dead, and then burial in urns. This
developed into what was called the "Urnfield Culture". The Urnfield culture lasted until the start of
the Halstaat period, when the Celts began the practice of inhumation, or full body burial.
The start of the inhumation burials also began the practice of object burial with the dead. The Celts belief in an afterlife was so strong that they would put off the payment of debts until they met on the other side. So, the idea of burying objects that would be of help on the other side wasn't so unusual. Swords, chariots, jewelry, and even wine flagons were sent on the journey with the deceased.
In the case of one female buried in Burgundy, she was buried with all of the pieces of the feast of her funeral. In her grave were wine storage vessels, jugs, bowls, and cups, imported from various areas of the civilized world. A good deal of jewelry also was included, including amber necklaces, brooches, and a large gold necklace. In another grave, most likely of a doctor, three tools associated with the profession were found-a probe, a retractor, and a trephining saw, which was used in brain surgery.
Julius Caesar, who wasn't the most reliable of witnesses, said that at some burials, slaves and favored retainers were burned with their masters.
With the development of archeology in the 19th century, the graves of many Celtic settlements helped reveal how the Celts both lived, and died.