Since the Plantation of Ulster in the early 17th Century, Ulster-Scots have played an important part in the history of the province, the British Isles and the world as a whole. Ulster-Scots and their descendants have played major roles in:
- The defence of Londonderry and the Williamite campaign in Ireland
- The signing of the American Declaration of Independence (most notably Charles Thomson, in whose hand it is drafted)
- The Congress of Vienna (Viscount Castlereagh)
- The defence of the Alamo (Davy Crockett, Jim Bowie) & The Battle of San Jacinto (Sam Houston)
- The Treaty of Versailles and the creation of the League of Nations (Woodrow Wilson)
- The Apollo 11 and 15 moon landings (Neil Armstrong & James B. Irwin)
The beginning of the 18th Century saw the start of a significant migration of Ulster-Scots to America. During the course of that century, an estimated 250 -300,000 Ulster-Scots (mainly Presbyterians) made the journey across the Atlantic Ocean. A combination of religious disability, economic factors and the prospect of a better life in the “New World” enticed many from Ulster to seek a new life in America, where they would later become known as the Scots-Irish.
Other favoured destinations for Ulster-Scots emigration have been Canada, Australia and New Zealand. These migrations occurred throughout the latter part of the 19th Century and into the 20th Century.