Aurora is a city in Marion County, Oregon, United States. Before being incorporated as a city, it was the location of the Aurora Colony, a reliā¦Aurora is a city in Marion County, Oregon, United States. Before being incorporated as a city, it was the location of the Aurora Colony, a religious commune founded in 1856 by William Keil and John E. Schmit. William named the settlement after his daughter. The population was 1,133 at the 2020 Census. It is part of the Salem Metropolitan Statistical Area.