Metamorphism in the age range Wenlock to mid-Devonian, when it can be recognized, appears to have accompanied some of the most intense phases of convergent tectonics in the orogen. Very different styles of metamorphism in different regions suggest different tectonic settings. In Scandinavia deep subduction and imbrication of the Baltic continental margin beneath N America (?), with little or no plutonism, produced a regional pattern leading to high temperature eclogites and granulites. In the British Isles, Canada and Maine, broad greenschist, prehnite-pumpellyite and lower-grade metamorphism accompanied the closure of Iapetus, with local higher-grade punctuations associated with widespread plutonic activity. In France, locally in Newfoundland, in southern New England and in part of the southern Appalachians both plutonic heating and intense deformation were involved in metamorphism to the amphibolite and locally the granulite facies, complicated in France by eclogites and locally by glaucophane schists.