Carlos is joined here by Sharon Shannon, with who he has shared many recordings and concerts.
This Galician tune for some reason sounds quite close to country or bluegrass. Who knows why, but it is true that even if those genres owe a lot to Irish or Scottish music, they also have a Spanish component (as explored by Willie Nelson, for instance), either directly when those territories were part of it, or via Mexico in more recent times.
Another more recent explanation for similar tunes would be the movies. Paddy Moloney always called this traditional Galician polka “The Big Country” (last tune in the video).
That same polka was played at the Kennedy Center, in Washington D.C., to celebrate the Irish Gala, with the US and Ireland administration authorities. One of the guests backstage was Ricky Skaggs, who immediately came to talk to Carlos after listening, to say it sounded like country music.