Ireland

The Republic of Ireland (Irish: Poblacht na hÉireann) was a pre-War country in western Europe.

Background
No details are known about the state of the Republic of Ireland after the Great War.

But considering that the Irish republic flag is found multiple times in the Commonwealth, a flag which, while was created in 1830, didn't enter common usage until Ireland became independent in 1922 and later became a republic. This strongly suggests Ireland did form a republic in Fallout's divergent timeline.

Ireland in Fallout

 * Colin Moriarty and Moriarty senior originated in Ireland but when Colin was a child they immigrated to the former United States.
 * John L. Sullivan is of Irish descent, has knowledge of Irish folk lore, and has an Irish accent.
 * Patrick the Celt is descended from Americanized Celts and keeps his heritage alive by collects clothing, food, stories, songs, and knowledge of celtic history. He knows the Irish song Na Gheala Mbeadh (Which is very poor Irish for "The Light Would". Possibly a mistranslation of 'Mo Ghile Mear' 'My Gallant Darling').
 * Dunwick's Irish Red was an Irish red ale manufactured and distilled by the Dunwik company prior to the Great War. It can't be found in any game; however, the logo for it can be found on beer taps across the Mojave Wasteland.
 * In 1897 Irish engineer John Philip Holland created the Modern submarine design.
 * In 1847 group of Irish volunteers, including U.S. Army deserters, joined the Mexican side in the Mexican–American War. These soldiers, known as Los San Patricios or Saint Patrick's Battalion.
 * In the underpass near the Nipton Road reststop there is a piece of graffiti which states "The centre cannot hold", a quote from the Irish poet WB Yeat's poem "The Second Coming."