According to The Corrs official website, Sharon is quoted as saying:
"I wrote it in Malibu on piano when we were recording Talk on Corners. It sat around for a long time and then the BBC were looking for some music for their big Autumn drama about the 1916 Easter Rising in Ireland. It has a very Irish melody and we added the tin whistle and so on and it fitted the bill."
Steven McDonald wrote for AllMusic that "Rebel Heart" "stirs itself up full-bloodily to provide the album with an anthem".[3]