Hello Dobwhite,
My name is Clare. My mother's mother's family are White's. My White/Whyte family hail from a small place called Derrainey (various spellings found). It is in the parish of Clonrush. It was in the county of Galway until the 1890s, then it was transferred into the county of Clare, which it is in now.
https://www.townlands.ie/clare/leitrim/clonrush/drummaan/derrainy/In the Clonrush graveyard, the oldest grave of the White family of Derrainy there dates back to the 1810s. They are James (d.1812) and Eleanor (d.1819) White of Derrainey.
https://www.clonrush.net/Pic%20130.htm The flagstone was put on the grave by their son Matthew White of Ballyhinch. Ballyhinch is the townland west of Derrainy. After this time there are many White families in the area.
Family folklore tells that the Whites came to Connacht during the time of the Cromwellian war from Waterford or Wexford. I found on TCD that Nicholas White had land in Quos (Coose) by 1670. Coose is also another townland just north of Derrainy. At that time Derrainy was mostly bog. I do not believe Nicholas lived in Galway but just owned land.
http://downsurvey.tcd.ie/landowners.php#l4=White,+Nicholas&mc=52.983064,-8.36558&z=12Anyways, I have done my DNA for myself and my Mother and I share DNA with a member (a Margaret Lesley Beck) that traces her family back to Elizabeth White of Scarnagh, father Matthew White who married a Thomas de Renzi of Ferns. I googled Scarnagh and your post came up. So here I am writing to you. I just wanted to know on your research have you come across Whites that went west. Would of course love to find a connection but I myself can't find a connection back on my Whites. I think with your John White being around 1625 my Whites might be related to your Whites that moved later to Connacht.
Any information you can give, would be great. Thanks, Clare