I get annoyed when people claim that songs/tunes are either "Irish" or (even worse) "Celtic" when they are clearly not and get all indignant when they are shown evidence of their true origin.

I've always assumed this tune actually is Irish but given the tendency for some people to claim that every traditional song or tune from the British Isles must be Irish or "Celtic" (yuk! How I hate that term) I thought I would check and see what I could find.

From a quick search on the internet, I found this

"...was probably composed in the mid-1800s. It was first notated in 1839 by Ed Bunting, who first heard it from a Miss Murphy of Dublin."

The source was a site of free flute music so would need further checking but seems reasonable. Of course it does not give the ultimate origin - which could well be untraceable - but it does suggest that it's been around in Ireland for long enough to reasonably be called Irish.

As to time signature I'd always assumed it to be in 6/8 and certainly the sources I originally found were all 6/8 but it's easy to "convert" a 6/8 tune to 3/4 and play it as a waltz. For dancing that's fine but if you do it as an air, you can easily lose something as the stress patterns for 6/8 and 3/4 are different.