The making of Pangea is the result of large-scale amalgamation of continents and micro-continents, which started at the end of the Neoproterozoic with the formation of Gondwana. As pieces were added to Gondwana on its South-American, Antarctica and Australia side, ribbon-like micro-continents were detached from its African and South-Chinese side: Cadomia in the late Neoproterozoic, Avalonia and Hunia in the Ordovician, Galatia in the Devonian and Cimmeria in the Permian. Cadomia was re-accreted to Gondwana, but the other ribbon-continents were accreted to Baltica, North-China, Laurussia or Laurasia. Finding the origin of these numerous terranes is a major geological challenge. Recently, a global plate tectonic model was developed together with a large geological/geodynamic database, at the Lausanne University, covering the last 600 Ma of the Earth's history. Special attention was given to the placing of Gondwana derived terranes in their original position, using all possible constraints. We propose here a solution for the Variscan terranes, another paper deals with the Altaids. The Galatian super-terrane was detached from Gondwana in the Devonian, during the opening of Paleotethys, and was quickly separated into four sub-terranes that started to bypass each other. The leading terranes collided at the end of the Devonian with the Hanseatic terrane detached from Laurussia. In the Carboniferous, Gondwana started to impinge onto the amalgamated terranes, creating the Variscan chain and the Pangean super-continent. East of Spain Paleotethys remained opened until the Triassic, subducting northward under Laurasia. Roll-back of the Paleotethyan slab triggered the collapse of most of the European Variscan orogen, which was replaced by series of Permian rifts, some of them becoming oceanized back-arc basins during the Triassic. Major force changes at the Pangean plate limits at the end of the Triassic provoked its break-up, through the opening of the proto-Caribbean, central-Atlantic, Alpine-Tethys oceanic seaways.

The Altaids, one of the largest and long-lived accretionary orogens in the world, developed from ca. 600 Ma to 250 Ma by the multiple accretions of terranes of different origin, chiefly microcontinents and island arcs. Considerable geological information supported by geochemical, radiometric and isotopic data suggest that modern geodynamic processes such as seamounts/plateau accretion, ridge-trench interaction, the formation of supra-subduction ridges and back-arc basins, arc-arc collisions and oroclinal bending were responsible for the evolution of the Altaid archipelagos. Because of the paucity of palaeomagnetic and radiogenic data it is still not possible to present a definitive palaeo-reconstruction of the Altaids. Nevertheless, considering the voluminous literature appearing today on the Altaids, it is timely and appropriate to present a review of current understanding of the many inherent tectonic problems, some of which are controversial.

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