Ulster is separated from Scotland by the narrow North Channel, which at one point is only 12 miles (19 kilometres) wide. Historically, this channel has been a link rather than a barrier, and from the earliest times to the present it has witnessed and carried a constant stream of traffic of people and ideas between the two coasts. Geography and history have combined to produce a strong Ulster-Scots community in Ulster. 

The most significant migration to have occurred between these areas was the successful Plantation of Ulster in the first half of the seventeenth century. Its consequences have been enduring.

These hardy and determined Scots settlers brought many innovations to Ulster including urbanisation, new agricultural practices and livestock, new building styles and techniques, language and culture. Their arrival also brought new surnames, a new religion and, of course, a change in politico-historical allegiance. As a result, Ulster would go on to have a radically different blend of peoples and traditions than the rest of Ireland.