The Iron Age in Estonia, spanning from around 500 BCE to 450 CE, is divided into two periods: the Pre-Roman Iron Age and the Roman Iron Age. During the Pre-Roman Iron Age (500 BCE – 1st century CE), the earliest iron objects were imported, but by the 1st century, iron smelting from local marsh and lake ore had begun. Settlements were often built in naturally protected areas, with temporary fortresses for defense. This period also saw the introduction of square Celtic fields and new burial practices, including quadrangular burial mounds. These changes in burial customs, along with the use of stones marked with magical symbols for crop fertility, indicate the early stages of social stratification.
The Roman Iron Age (50–450 CE) brought further external influences, particularly from the Roman Empire. Although direct contact was limited, Roman coins, jewelry, and other artifacts found in Estonia reflect this influence. In southern Estonia, the abundance of iron objects suggests closer connections with mainland Europe, while the coastal and island regions maintained stronger ties with neighboring regions across the sea. By the end of the Roman Iron Age, distinct tribal areas had emerged in northern, southern, and western Estonia, with each region developing a unique sense of identity.