Original sentence: - Many people, especially some unionists, may refer to Northern Ireland as Ulster – although this is officially wrong, as the Irish province of Ulster is a nine county entity incorporating the three counties of Donegal, Cavan and Monaghan, which are in the Republic of Ireland, along with the six northern counties.The term Ulster (and "the Province") are sometimes preferred by Unionists, sometimes because it can suggest an origin of the polity of Northern Ireland that pre-dates 1922, referring back to the Act of Union 1800, the Glorious Revolution of 1689, the Plantation of Ulster in 1610, the ancient migrations between Ulster and Scotland, and even to biblical tradition.This use for the term Ulster by Unionists to mean Northern Ireland, is offensive to members of the Nationalist community, as Ulster includes, but is not exclusive, to Northern Ireland.for these reasons, it is understandable that certain local place names are still be in dispute: for example see Derry/Londonderry name dispute
Edited sentence: Certain local place names are also still in dispute: for example see Derry/Londonderry name dispute.Many people, especially some unionists, sometimes refer to Northern Ireland as Ulster, although from the 15th century the Irish province of Ulster was a nine county entity incorporating the three counties of Donegal, Cavan and Monaghan (which are now in the Republic of Ireland) along with the six northern counties.The term Ulster (and "the Province") are sometimes used by Unionists and can suggest that the polity of Northern Ireland is a continuation of an entity that, in one form or another, pre-dates 1922, referring back to the Act of Union 1800, the Glorious Revolution of 1689, the Plantation of Ulster in 1610, the ancient migrations between Ulster and Scotland, and even to biblical tradition.This 9-county definition is still preferred by Irish nationalists although it has no official recognition.This use for the term Ulster by Unionists to mean Northern Ireland, is offensive  to members of the Nationalist community, as to them Ulster extends beyond Northern Ireland