The Gawler Craton hosts one of the world’s great iron oxide-copper-gold deposits and districts, and despite evidence for widespread Archean basement, almost all of the rocks exposed at the surface (or near surface) are Proterozoic in age. In particular, the Paleoproterozoic to Mesoproterozoic evolution of the region is increasingly well documented, including major tectonometamorphic and magmatic events that occurred at c. 2440-2420 Ma, c. 1730 - 1690 Ma, and c. 1630 - 1590 Ma; along with significant copper-gold mineralisation associated with the c. 1590 Ma events. However, what is perhaps less well considered is what possible legacy effects the widespread Archean basement has had on the subsequent tectonic/magmatic/thermal systems. We consider several examples across the region, where Archean rocks and indeed possible Archean structures have influenced Proterozoic processes. In the region with largest exposure of basement rocks, the Eyre Peninsula, Archean rocks have been confirmed in the c. 3150 Ma Cooyerdoo Granite and the c. 2860 Ma Coolanie Gneiss. Using these known exposures and integrating geophysical, inherited zircon and isotopic evidence, studies have shown that a Mesoarchean basement is likely to underlie much of southern Gawler Craton, despite the surface geology being dominated by Paleo- to Mesoproterozoic rock packages. Key fault zones in the Gawler Craton may also be associated with important boundaries established during the Archean. Faults such as the Elizabeth Creek fault separate late Archean and earliest Paleoproterozoic rock packages, have significant Moho topography, and magnetotelluric conductivity anomalies and appear to influence the location of Mesoproterozoic magmatism and mineralisation. Finally, we consider the case of the c. 1620 Ma St Peter Suite, a bimodal igneous complex in the SW of the region. Based on the (modestly) ‘juvenile’ Nd isotopic composition, some studies suggest the St Peter Suite is related to a subduction zone process, either continental or even ocean arc setting. However, given the evidence for Archean basement in surrounding areas, and considering c. 1.7 Ga inherited zircon and the enriched nature of the mafic geochemistry, it is equally plausible that the suite is another example of a typical Australian Proterozoic granite suite that developed as a result of (backarc?) extension of the underlying Archean lithosphere. In these examples we suggest the Gawler Craton is likely underlain by a lower crust and lithosphere with minimum age of c. 3.1 - 2.8 Ga, which has been rifted, dissected, and reworked by intensive Proterozoic activity. The anomalously enriched heat producing elements that characterise the eastern Gawler Craton in particular, may be indicating something fundamental about the geochemical make up of this ‘original’ Archean crust, or alternatively, the extent and style of Proterozoic reworking. The recognition of an Archean lithospheric root in the Gawler Craton conforms to models that suggest many terranes globally are underlain by Archean lithosphere, with variable degrees of reworking. The key implication being major lithospheric boundaries internal to Proterozoic terranes can be zones of pre-existing weakness, being susceptible to reactivation including enhanced magma and fluid flow, which can ultimately be expressed in the upper crust as hydrothermal (or magmatic) mineral deposits.