Oi Dai is Värttinä's 3rd album, and the first after they re-formed in 1990 after losing many members. It was released in 1991 in Finland by Spirit/Polygram. It was a great success, and led to Värttinä touring throughout Europe. In 1994, it was released in the United States by Xenophile Records. It was later re-released in the US by NorthSide.