Vindaloo is a very popular in Goan cuisine found throughout Indian restaurants in the west but less popular in India itself.
Vindaloo is derived from Portuguese words vinho (wine) and Alhos (garlic). Vindaloo evolved from Portuguese dish "Carne de Vinha d' Alhos" (meat wine and garlic), which was brought to Goa by them. Portuguese dish usually contains red wine and garlic stewed with pork. Goan Vindaloo dish has similar ingredients but with additional ingredients with Indian flavors such as hot chili. curry powder, and other spices.
Interestingly, many Vindaloo recipes as well as restaurant dish now contain potatoes. It may be due to confusion among non-goan Indian chefs several decades ago because the word "aloo" means "potato" in Hindi. Now potatoes in Vindaloo may just be new evolution of this already evolved ancient dish.