A bracteate (from the Latin bractea, a thin piece of metal) is a flat, thin, single-sided gold medal worn as jewelry that was produced in Northern Europe predominantly during the Migration Period of the Germanic Iron Age (including the Vendel era in Sweden). Bracteate coins are also known from the medieval kingdoms around the Bay of Bengal, such as Harikela and Mon city-states. The term is also used for thin discs, especially in gold, to be sewn onto clothing in the ancient world, as found for example in the ancient Persian Oxus treasure, and also later silver coins produced in central Europe during the Early Middle Ages.

Gold bracteates commonly denote a certain type of jewelry, made mainly in the 5th to 7th century AD, represented by numerous gold specimens. Bead-rimmed and fitted with a loop, most were intended to be worn suspended by a string around the neck, supposedly as an amulet. The gold for the bracteates came from coins paid as peace money by the Roman Empire to their Northern Germanic neighbors.

Many of the bracteates feature ruler portraits of Germanic kings with characteristic hair that is plaited back and depictions of figures from Germanic mythology influenced to varying extents by Roman coinage while others feature entirely new motifs. The motifs are commonly those of Germanic mythology and some are believed to be Germanic pagan icons giving protection or for divination.

Often depicted is a figure with a horse, birds and sometimes a spear – that some scholars interpret as a representation of the Germanic god Wodan – and aspects of the figure that would later appear in 13th century depictions as Odin such as the Poetic Edda. For this reason the bracteates are a target of iconographic studies by scholars interested in Germanic religion. Several bracteates also feature runic alphabet inscriptions (a total of 133 inscriptions on bracteates are known, amounting to more than a third of the entire Elder Futhark corpus). Numerous Bracteates feature swastikas as a common motif.

The typology for bracteates divides them into several letter-named categories, a system introduced in an 1855 treatise by the Danish numismatist Christian Jürgensen Thomsen named Om Guldbracteaterne og Bracteaternes tidligste Brug som Mynt and finally defined formally by the Swedish numismatist Oscar Montelius in his 1869 treatise Från jernåldern:

More than 1,000 Migration Period bracteates of type A-, B-, C-, D-, and F are known in total (Heizmann & Axboe 2011). Of these, 135 (ca. 11%) bear Elder Futhark inscriptions which are often very short; the most notable inscriptions are found on the Seeland-II-C (offering traveling protection to the one who wears it), Vadstena (giving a listing of the Elder Futhark combined with a potential magical inscription) and Tjurkö (featuring an inscription in scaldic verse) bracteates.

To these can be added the ca. 270 E-bracteates (Gaimster 1998), which belong to the Vendel Period and thus are slightly later than the other types. They were produced only on Gotland, and while the earlier bracteates (apart from a few English pieces) all were made from gold, many E-bracteates were made from silver or bronze.

The German historian Karl Hauck, Danish archaeologist Morten Axboe and German runologist Klaus Düwel have worked since the 1960s to create a complete corpus of the early Germanic bracteates from the migration period, complete with large scale photographs and drawings. This has been published in three volumes in German named Die Goldbrakteaten der Völkerwanderungszeit. Ikonographischer Katalog. A catalogue supplement is included in Heizmann & Axboe 2011.