"Southern Ireland" Doesn't Exist: It's the Republic of Ireland

There is no country or official region called "Southern Ireland." The island of Ireland comprises two political entities:

• Northern Ireland: Part of the United Kingdom (capital: Belfast).
• Republic of Ireland: Sovereign independent country (capital: Dublin), covering ~80% of the island.

Common Usage

• People sometimes informally say "the South" or "the Republic" to distinguish from Northern Ireland.
• Officially: Ireland (constitutional name) or Republic of Ireland (description).
• EU/UN/ISO: "Ireland" (IE, IRL).

Why It Matters

"Southern Ireland" was a short-lived British administrative term (1921–1922) for the area that became the Irish Free State. It has no legal or political status today. Using it can imply the Republic is a sub-region of the UK, which is incorrect and offensive to many.

Correct terms: "Republic of Ireland," "Ireland," "the South" (informal), "the 26 counties" (historical).