Gaya (가야; 加耶, 伽耶, 伽倻), also known as Garak (가락; 駕洛, 迦落), Gara (가라; 加羅, 伽羅, 迦羅, 柯羅), Garyang(가량,加良), or Guya (구야, 狗耶) was a confederacy of chiefdoms that existed in the Three Kingdoms era in ancient Korea.
Gaya is thought to have arisen from a more ancient confederacy of chiefdoms called Byeonhan. The nature of the transition is not clear from historical sources. However, on the basis of archeological sources as well as limited historical indications, scholars such as Cheol (2000) have identified the late third century AD as a period of transition from Byeonhan to Gaya. At this time records show increasing military activity and changed funerary customs. This would also coincide in part with the decline of the Chinese commanderies on the peninsula. Cheol (2000) further argues that this was associated with the replacement of the previous elite in some principalities (including Daegaya) by elements from the Manchurian kingdom of Buyeo, who brought a more militaristic style of rule.
According to a legend recorded in the Samguk Yusa, in the year 42, 6 eggs descended from the heaven with message that they would be kings. 6 eggs hatched and 6 boys were born, and within 12 days they grew mature. One of them, named Suro (수로; 首露), became the king of Geumgwan Gaya (금관 가야), and the other five founded the other five Gayas, namely Daegaya (대가야), Seongsan Gaya (성산 가야), Ara Gaya (아라 가야), Goryeong Gaya (고령 가야), and Sogaya (소가야).
Situated around the mouth of the Nakdong River, an area with fertile plains, access to the sea, and rich iron deposits, Gaya had an economy based on agriculture and fishing as well as trade. It was particularly known for its ironworking, as Byeonhan had been before it. Gaya exported abundant quantities of iron armor and weaponry to Baekje and the kingdom of Wa in Yamato period Japan. In contrast to the largely commercial and non-political ties of Byeonhan, Gaya seems to have attempted to maintain strong political ties with these kingdoms as well.
The various Gaya mini-states formed a confederacy in the 2nd and 3rd centuries centred around Geumgwan Gaya in modern Gimhae. After a period of decline, the confederacy was revived around the turn of the 5th and 6th centuries, this time centred around Daegaya of modern Goryeong, but it was unable to defend itself for long against Silla and Baekje. In 562, Daegaya, the last of the Gaya states, fell to Silla.
The nature of the relationship between the Japanese kingdom of Wa and the Gaya states has been a matter of extensive controversy. Japanese scholars traditionally have argued, on the basis of various sources including the Nihonshoki, that Gaya was a colony or tributary of Wa. Korean scholars have rejected this, on the basis of Korean sources which make no mention of Japanese suzerainty. Today, most scholars regardless of nationality concede that the relationship between Gaya and Wa was close, but not colonial.
Cheol, S.K. (2000). Relations between Kaya and Wa in the third to fourth centuries AD. Journal of East Asian Archeology 2(3-4), 112-122.