Names with an Irish, Scottish or Welsh touch

Ireland

Bran is the name of the great Irish warrior MacCumhail's dog.   

Sceolan (skol wan)  is the name of MacCumhail's second dog

Cúchulainn (Ku-Kullen) was the name of the Irish mythical warrior .  

Morrigan is the Goddess of war in Celtic mythology

Seamus is James in English

Finian is from the Broadway show Finian’s Rainbow, a story about an Irish family in the America.  The play was later made into a movie directed by Coppola, starring Fred Astaire

Conan is from Saint Conan, the Bishop of the Isle of Man and a missionary 

Madra (Mod-Rah) is Gaelic word for dog

Brandon is from Ireland's highest mountain

Scotland

Alisdair  is the Scottish Gaelic word for Alexander

Barclay means the strong birchwood

Brodie  means little ridge

Conall means strong wolf

Dougal means dark stranger, may fit a dog with a dark shiny coat 

Fergus means a man or woman of vigour

Greer is from the Latin word gregorius

Laddie means young man

Mungo means gentle. Mungo was also the nickname of Saint Kentigern. 

Alba is the traditional name for Scotland

Grizel (or Grizelda) means grey battle

Mor (or Morag) -s the old Scottish word for great or exceptional

Wales

Cari means beloved

Efa is Eva in English, means life

Eira means snow

Mali means star of the sea, Molly in English

Seren is the name of a Celtic goddess of hot springs.

Arawn is the name of the king of Annwn in welsh mythology, means unrestrained wildness, may suit a very energetic pet

Bryn means hill/mount

Maddox is the son of Madoc and Madoc means fortunate. Maddox is the mythical Welsh prince who colonized North America before Columbus.