A phenylene ether oligomer has repeating units of the structure and less than 30 weight percent of repeating units derived from a monohydric phenol having identical substituents in the 2- and 6-positions, wherein the phenylene ether oligomer includes a vinyl benzene ether end group, an amine end group, maleimide end group, a norbornene end group, an anhydride end group, or a combination comprising at least one of the foregoing. The phenylene ether oligomer can be used to provide a curable composition. The curable composition can be cured to provide a thermoset composition. Articles comprising the thermoset composition are also described.