Whenever you want to look up some place, go to www.bartleby.com/69/.It is a gazetter, and will give you lots of information on places in North America.
Here is what it said about Independence:
Independence, town (1990 pop. 4,425), Polk co., NW Oregon, on Willamette R., 8 mi/12.9 km SE of Dallas; 44°51'N 123°11'W. RR junction. Agr. (grapes, hops, corn, beans, grain; poultry, hogs, sheep, cattle); dairy prods.; nurseries. Ankeny Natl. Wildlife Refuge to SE; Helnick State Park to SW. Inc. 1874.