Ulster Ulster The term Ulster to describe Northern Ireland is politically loaded. Ulster was one of the ancient kingdoms of Ireland and it traditionally encompasses the six counties of what is now Northern Ireland plus Donegal, Cavan and Monaghan, which have been in the Republic of Ireland since 1922. Even the term Northern Ireland is somewhat loaded as the northernmost tip of the island of Ireland is actually in the Republic - the Inishowen peninsular in county Donegal.
Unionists are much happier to describe Northern Ireland as Ulster.
The media often do because it is shorter and provides an alternative to repeating 'Northern Ireland'. Nationalists and Irish Republicans have sought to emphasise the fact that Ireland is all one country and that Northern Ireland is an artificial creation.