Edward Nilsen

Hello, I need help tracking down the parents and ancestors of my Great Great Grandfather Edward Nilsen. He was born in Norway on 23 January 1874, but I have no idea where, though a ship manifest for the SS Philadelphia in 1904 lists him as coming from Stavanger. He immigrated to the US in 1889 and was naturalized in 1905. He was a marine engineer and spent a great deal of time on ships. He was married to Marie Adelaide Rabbach, had one daughter named Myrtle Nilsen, and lived for a bit in Harris County, Mississippi but lived most of his life in New Orleans. He died in 1969. I have hit a brick wall here, and unfortunately, I do not think my Grandfather remembers much of Edward's history. Any help or tips would be greatly appreciated. Thanks, Coby Treadway