While the exact origins of Hash Brown Potato Soup are unclear, hash browns themselves have a long history. The term "hash brown potatoes" was first mentioned by food author Maria Parloa in her 1888 book "Kitchen Companion." They became a popular American breakfast staple in the early 20th century. Combining hash browns with a creamy soup base likely evolved from the traditional potato soups found in many European cuisines, particularly those of Ireland and Germany, where potatoes are a dietary staple.