When did the first department store open in the US?

An Irish immigrant in New York opened a business on Broadway called the Marble Dry-Goods Palace in 1846. This was the first Department Store. The Palace was the first to bring together a huge range of produce and was so successful that it soon covered a whole block on Broadway and had a staff of two thousand. By 1862, Stewart relocated to an eight-storey building near by and renamed it A.T. Stewart's Cast-Iron Palace. This was (and for many years remained) the largest retail operation in the world.