It is named after the first Colonial Treasurer Osmond Gilles who owned a sheep station adjoining the Torrens River.[2] Gilles Plains was predominantly a hay growing area of Adelaide through its early years.In 1874, it had the largest hay farm in South Australia owned by J.[3] Gilles Plains is in both the City of Port Adelaide Enfield and City of Tea Tree Gully local government areas, and is in both the South Australian House of Assembly electoral districts of Florey and Torrens.St Pauls College is on Grand Junction Road.
Aerial image of northern part of Gilles Plains, looking north. Grand Junction Road is the east–west road at the top, forming the boundary of the suburb. To the north is Valley View. The green rectangle to the left is St Paul's College, and Wandana Primary School is at the oval in the middle.