This beautiful painting is entitled “Oisin Rides to the Land of Youth”. Painted in 1936 by American artist Newell Convers Wyeth. it represents a more Anglophile view of Irish mythology that many non-Irish creators continue to produce today.
You can’t fault Convers Wyeth however. A talented illustrator and painter, he produced a huge body of work in his time. This included well over a hundred ‘action/adventure’ style images for book covers.
I can imagine, he’d be in high demand today.