The old records at logainm.ie include Post Office notes like this:
http://www.logainm.ie/Iomhanna/88/po57179-80_3.JPGQuote:
"The Jones family took their title from Ranelagh in Co. Wicklow, and though they lived for a time in Dublin, they moved in the early 18th Century to London where they built themselves a house at Chelsea. This naturally became known as Ranelagh House, and was later turned into the famous Ranelagh Gardens (1762) .... In 1766 one Hollister [...] started a pleasure-garden at Cullenswood, just outside Dublin, and called it Ranelagh Gardens. So the name of Ranelagh returned to Ireland."
I couldn't find a "Ranelagh" in Co. Wicklow, but there is a Kilranelagh, which is Cill Rannaileach in modern Irish.
Here's something taken randomly off the web:
Quote:
The Raghnal was a clan that held sway in the mid-1500's in the Wicklow Mountains and what is now South Dublin. In Gaelic, 'Raghnallach' means Raghnal's place.
There are other references to Raghnull and the like in the Post Office notes that tend to support "the Church of the Clan of Raghnall" as the derivation of Kilranelagh, at least.