Abstract Mississippian rocks of the Antler foreland basin in Nevada (western United States) record its evolution in detail, clarifying the timing and tectonic significance of the Antler orogeny. Synorogenic clastic sediments mark the initiation of tectonism; they arrived in Nevada from the north or northwest in late Early Mississippian (Osagean). An orogenic highland formed in northern Nevada in late Middle Mississippian (Meramecian), producing a regional angular unconformity and terminating deposition in the Antler foreland basin. Unconformably overlying Upper Mississippian (Chesterian) rocks provide tight age control for the redefined “Antler orogeny” sensu stricto. Palinspastic restoration of Sr isotopic data reveals a projecting step in the Laurentian margin in northern Nevada. The Antler orogeny resulted from late Middle Mississippian sinistral-oblique convergence at this step. Continuing oblique convergence produced the subsequent late Paleozoic basins, structures, and unconformities in northern Nevada. The Roberts Mountains allochthon is translated material from farther north emplaced onto the margin. Its basal bounding fault, long mapped as the “Roberts Mountains thrust,” is in fact not a single continuous fault, motion on it was not synchronous, and displacement on many fault segments mapped as the Roberts Mountains thrust postdate the late Middle Mississippian. We therefore propose that the term “Roberts Mountains thrust” be abandoned. This new paradigm not only explains anomalous characteristics of the Antler orogeny but also illustrates criteria for recognizing oblique convergence at other ancient plate margins.