How did Ireland get its nickname Erin?

Ireland is often referred to by its poetic name, Éire, which is pronounced "air-eh". The name Éire is derived from the Old Irish word Ériu, which was the name of the goddess of Ireland in Celtic mythology. The name Erin is an Anglicized version of Éire.

The name Ireland itself comes from the Old English word Īrland, which is derived from the Germanic word eireland. The word eireland is thought to be a combination of the words "eire", meaning "west", and "land", meaning "land". So, Ireland literally means "land of the west".