Throughout this period there were vivid and striking manifestations of religious beliefs, ritual behaviour, and artistic activities. One of the most remarkable phenomena was hoarding. Objects, usually in large numbers, were deliberately hidden in the ground or deposited in water in the form of a hoard. Hoards were known in a modest form during the Neolithic Period, and in some areas, such as Scandinavia and France, there continued to be a few large hoards in the Iron Age; but it was in the Bronze Age that hoarding became a common phenomenon of great social and economic importance. The contents of the hoards varied; they ranged from two to several hundred items or consisted of only one deliberately deposited object, such as the single swords found in the River Thames. They might contain several objects of the same type or of many different types. They were commonly placed in association with wet areas—such as rivers, bogs, and meadows—or located under or near large stones, including in old megalithic tombs. They were seldom parts of settlements, but they have been found in wells, such as at Berlin-Lichterfelde, in Germany. They also may have come to function as a foundation deposit for a later settlement, as was the case at Danebury, in southern England, where an Iron Age hill fort was placed at the location of a Late Bronze Age hoard. Hoards were relatively infrequent during the earliest part of the Bronze Age, when they were found mainly in southeastern Europe, Bavaria, and Austria and contained flat axes and neck rings. Hoarding reached its peak during the later part of the Early Bronze Age and the Middle Bronze Age, when the activity spread throughout Europe and became an established phenomenon in most of its communities. In the Middle and Late Bronze Age, large numbers of hoards were deposited, and a substantial number of bronze objects were in this way consumed and withdrawn from circulation. Late Bronze Age hoards from Romania, among the largest ever, contained up to four tons of bronze objects. At the same time, large collections of unused tools, newly taken from their molds, were deposited together in France.

Hoarding is one of the more unusual elements of Bronze Age Europe, and it is difficult to explain. The activity consumed large parts of the wealth of these societies without apparent benefits. Traditional explanations have divided them into different types with varying function. The lack of settlement association means that they were not originally foundation deposits, such as are known from the Roman period. They must, therefore, be explained either in terms of metalworking procedures or as having a ritual or religious meaning. Hoards that could have been retrieved from their hiding place have been interpreted, depending on their contents, as hidden treasure, merchants’ stock, or items intended for recycling by the smiths. Hoards that could not possibly have been retrieved must have had ritual or religious significance, or, alternatively, they were acts of conspicuous consumption of wealth in a potlatch ceremony. This would enhance the position of the owner and, incidentally, would also ensure the flow of imports and the value of bronze. But a functional interpretation of hoards as a kind of stock cannot account for why these hoards were so often not retrieved. Thousands of hoards were made during the Bronze Age, and enormous riches were disposed of through these activities. In spite of their internal differences and variations in terms of location, composition, and amounts, it is likely that ritual behaviour and cultural meaning were always major components of this practice. There is, however, only little indication of what that meaning was. The association with water, which became more pronounced through time, could suggest water-related rituals and has been interpreted as relating to fertility rites and agricultural production. Because the location and composition of hoards vary locally as well as through time, however, they may embody more than one meaning.

Only a few areas saw instances of hoarding in the Iron Age, and their forms were distinctly different from those of the Bronze Age. The most obvious example is the votive deposit at Hjortspring, Den., where a large wooden boat equipped for war with wooden shields, spears, and swords was destroyed and deposited in a small bog. The events behind these hoards were known to Classical writers such as Tacitus and Orosius, who gave accounts of war offerings by Germanic and Cimbrian tribes, respectively. They describe how the weaponry confiscated in war was destroyed and deposited in victory ceremonies. The Iron Age hoards of northern Europe had clear associations with war, the types and numbers of objects deposited together are incomparable with the Bronze Age hoards, and the ritual destruction of the entire assemblage was a new element.

The new hoarding ritual contained elements of conspicuous consumption, but its form and focus were different from previous activities. It developed shortly before the end of the 1st millennium, and it continued as a tradition among the Germanic tribes in northern Europe for several centuries. Another area with complex ritual ceremonies during the Iron Age is France. There are not many of these ritual places, but those that existed were large complex sanctuaries with continuous use over several centuries. One of these sites is Gournay-sur-Aronde, in northern France, a sanctuary used from 300 to 50 bce. The site consisted of a square enclosed by a ditch and palisade with a number of large pits for exposing and displaying offerings at its centre and a number of wood-lined ditches along the edges. In the ditches were found the remains of hundreds of iron weapons, all deliberately and systematically destroyed, as well as fibulae and tools. There were also the remains of 208 animals and 12 humans. These remains indicate some of the ceremonial behaviour that had taken place on the site. All cattle had the muzzle cut off during offering, and their skulls were displayed on top of pits and ditches. The humans had been beheaded, and the bones were at some points moved from the central pits to the ditches and rearranged there according to different prescriptions. The archaeology shows that both the Bronze and Iron ages were periods of specific and unique ritual behaviour but also that their beliefs and norms were not uniform throughout each period. As the socioeconomic structures of these societies changed, their ideological structures underwent transformation.

Societies reveal themselves through their art. These expressions are, however, difficult to interpret, and much of this evidence from the past has disappeared. It is at the same time an essential source, giving insight into the artistry and sophistication of the people of these periods. The development of styles can be followed through the decoration of metal objects and ceramics, while a more distinct pictorial art is found in the rock art from many parts of Europe, in the wall paintings from Minoan Crete, and in the odd figures and scenarios engraved on a range of materials. Stylistic developments show the existence of workshops and schools, and the degree of influence they exercised reached into far corners of the Bronze and Iron Age communities. In the stylistic development during the Metal Ages, two phenomena are of particular interest. The first is the development of the sun-bird-ship motif of the Urnfield Culture. The origin of this motif, which featured bird-headed ships embellished with solar disks, is not known, but over a short period about 1400 bce it became common both as incised decoration and as plastic art throughout a vast area of eastern and central Europe. The similarity in execution and composition is remarkable and suggests a shared understanding of its meaning and the intensity of contact between distant areas.

The second point of interest is the change in style between the Hallstatt and La Tène periods. Throughout the Bronze Age and the Late Hallstatt Period, there were two distinct types of decoration in temperate Europe: the dominant geometric design of various compositions, including curvilinear styles, and the less common naturalistic style portraying humans and animals and used, for example, in rock art. At the end of the Hallstatt Period, at the beginning of the second phase of the Iron Age, a new decorative style, the La Tène style developed, and it rapidly replaced the geometric decoration. This style, as abstract as the Bronze Age one, was nonetheless substantially different. It incorporated flowing curved lines of floral designs with zoomorphic motifs filling the surfaces of the objects and increasingly used settings of semiprecious stones and coral. During the Iron Age this style flourished and branched out into different schools of great beauty. The style reached its mature form in the 4th century bce with the Waldalgesheim style, and, after this point, its most interesting branch was found in Britain, which saw a very individual development and where La Tène art continued to flourish after this style had passed its zenith on the Continent. The La Tène style was used on a variety of artifacts, such as gold and silver jewelry, swords and scabbards, shields inlaid with enamel, bronze mirrors, and beautifully executed containers in wood and ceramics.

The origin and spread of the different art styles have been the subject of much debate. Early Bronze Age geometric and linear motifs, in particular the use of double-axe and spirals motifs, looked to be the result of Mycenaean influences. The art of the Urnfield Culture was thought to be the result of an invasion of people from the east, bringing cremation and a new art style into Europe. La Tène art was associated with the Celtic people, and their spread throughout large parts of Europe was assumed to have brought this art to different areas. The genesis of the various artistic developments cannot easily be established; but they were not as unified a phenomenon as has been assumed, and local variations are prolific. Different art styles influenced each other and were spread widely through copies, exchange, and communication; but this was interspersed with periods of greater local diversity and less desire for contact and emulation.