This was not something fundamentally new in Ireland, however, as until 1979 Ireland had participated in a currency area with sterling for over one hundred and fifty years previously; the Irish currency and sterling were amalgamated at parity in 1826.
With the introduction of the Irish pound in the late 1920s, there was a no-margins one-for-one link between the Irish pound and sterling which prevailed until 1979. Coupled with complete freedom of capital mobility, this resulted in virtually the same levels of interest rates in Ireland and the UK.