An iterative inverse model of seafloor spreading data from the Mascarene and Madagascarbasins and the flanks of the Carlsberg Ridge describes a continuous history of Indian-AfricanPlate divergence since 84 Ma. Visual-fit modelling of conjugate magnetic anomaly data fromnear the Seychelles platform and Laxmi Ridge documents rapid rotation of a Seychelles Plateabout a nearby Euler pole in Palaeocene times. As the Euler pole migrated during this rotation,the Amirante Trench on the western side of the plate accommodated first convergence andlater divergence with the African Plate. The unusual present-day morphology of the AmiranteTrench and neighbouring Amirante Banks can be related to crustal thickening by thrusting andfolding during the convergent phase and the subsequent development of a spreading centrewith a median valley during the divergent phase. The model fits FZ trends in the north Arabianand east Somali basins, suggesting that they formed in India-Africa Plate divergence. Seafloorfabric in and between the basins shows that they initially hosted a segmented spreadingridge that accommodated slow plate divergence until 71-69 Ma, and that upon arrival of theDeccan-Réunion plume and an increase to faster plate divergence rates in the period 69-65 Ma,segments of the ridge lengthened and propagated. Ridge propagation into the Indian continentalmargin led first to the formation of the Laxmi Basin, which accompanied extensive volcanismonshore at the Deccan Traps and offshore at the Saurashtra High and Somnath Ridge. Asecond propagation episode initiated the ancestral Carlsberg Ridge at which Seychelles-Indiaand India-Africa Plate motions were accommodated.With the completion of this propagation,the plate boundaries in the Mascarene Basin were abandoned. Seafloor spreading between thistime and the present has been accommodated solely at the Carlsberg Ridge. © The Authors 2013. Published by Oxford University Press on behalf of The Royal Astronomical Society.