Recently I referred to my Icelandic accent coming on a treat. I lied. It really is more Swedish chef (think Muppets). Dearest isn't impressed either way.
My real accent when I think about it, is more Waitrose than Iceland, however. The voice of middle England. With a few renegade Welsh vowels left over from my youth.
I was brought up by Welsh parents on a council estate in Borehamwood. So not in the slightest bit posh. However, the Welsh accent was the first I heard and I stuck to it, or it stuck to me for many years.
My younger brother however, embraced the glottal stop (where water is pronounced wa-er, and bottle, bo-ul) so that he became no different from his peers.
If anyone asked me for directions, when I was a child, as soon as I spoke, they assumed I hadn't been in the area very long. I gave up explaining that I had been born and bred in Hertfordshire and took to saying that I came from Llanelli, South Wales which is where my grandparents lived.
As the years went by I developed an ability to adapt my accent. I found that when I finally left home to go to university in Stirling that my basic Welsh accent developed traces of Scottish which I find are reactivated every time I cross the border.
I remember, many years ago, as a student going to a party in Glasgow where one friend commented to another,
"I love the way she rolls her rrr s".
Back came the reply, "Ach, she canny help the way she walks!"