Gaelic Ireland (Irish: Eire Ghaidhealach) was the Gaelic political and social order, and associated culture, that existed in Ireland from the prehistoric era until the early 17th century. Before the Norman invasion of 1169, Gaelic Ireland comprised the whole island. Thereafter, it comprised that part of the country not under foreign dominion at a given time. For most of its history, Gaelic Ireland was a "patchwork" hierarchy of territories ruled by a hierarchy of kings or chiefs, who were elected through tanistry.
Economy
Gaelic Ireland was involved in trade with Britain and mainland Europe from ancient times, and this trade increased over the centuries. Tacitus, for example, wrote in the 1st century that most of Ireland's harbours were known to the Romans through commerce. There are many passages in early Irish literature that mention luxury items imported from foreign lands, and the fair of Carman in Leinster included a market of foreign traders. In the Middle Ages the main exports were textiles such as wool and linen while the main imports were luxury items.  Money was seldom used in Gaelic society; instead, goods and services were usually exchanged for other goods and services. The economy was mainly a pastoral one, based on livestock (cows, sheep, pigs, goats, etc.) and their products. Cattle was "the main element in the Irish pastoral economy" and the main form of wealth, providing milk, butter, cheese, meat, fat, hides, and so forth. They were a "highly mobile form of wealth and economic resource which could be quickly and easily moved to a safer locality in time of war or trouble". The nobility owned great herds of cattle that had herdsmen and guards. Sheep, goats and pigs were also a valuable resource but had a lesser role in Irish pastoralism.  Horticulture was practised; the main crops being oats, wheat and barley, although flax was also grown for making linen.  Transhumance was also practised, whereby people moved with their livestock to higher pastures in summer and back to lower pastures in the cooler months. The summer pasture was called the buaile (anglicized as booley) and it is noteworthy that the Irish word for boy (buachaill) originally meant a herdsman. Many moorland areas were "shared as a common summer pasturage by the people of a whole parish or barony".

Q: What was their economy based on?
A: In the Middle Ages the main exports were textiles such as wool and linen while the main imports were luxury items.

Q: Who did they trade with?
A: Gaelic Ireland was involved in trade with Britain and mainland Europe from ancient times,

Q: Did they trade with any other countries?
A: Tacitus, for example, wrote in the 1st century that most of Ireland's harbours were known to the Romans through commerce.
Did they trade for items or for money?
Money was seldom used in Gaelic society; instead, goods and services were usually exchanged for other goods and services.
Money was seldom used in Gaelic society; instead, goods and services were usually exchanged for other goods and services.