Transport variability in the south-western Indian Ocean (SWIO) is important for understanding inter-ocean heat transfer and the downstream effects of atmosphere-ocean dynamics on local climate.  In this study we look at remote drivers of SWIO variability, in particular those associated with El Niño-Southern Oscillation (ENSO).  By understanding the mechanisms of teleconnections via both atmosphere and ocean associated with El Niño/La Niña, referred to here as “mixed ENSO-teleconnections”, we show the potential for climate signals to be transmitted over considerable spatial and temporal scales.  To quantify the influence of ENSO on Indian Ocean dynamics and to describe the spatio-temporal patterns of covarying atmospheric and oceanic field variables over two oceanic basins, we use a Singular Value Decomposition analysis of Indian Ocean wind-stress curl anomalies and tropical Pacific Ocean sea-surface temperature anomalies from both observations and a climate model simulation from the NCAR CESM1.  We then reproduce Rossby wave signals mathematically by applying a simplified 1½-layer reduced gravity model to CESM1 model output over 150+ years to trace sea-surface height anomalies propagating along Rossby wave characteristics across the southern IO basin.  The simple mathematical modelling approach considers a decomposition of sea-surface height anomaly propagation associated with both baroclinic and barotropic Rossby wave generation.  These are further partitioned into components relating to interior wind-stress curl-driven Ekman-pumping and to the propagation of eastern-boundary sea-surface height anomalies (likely to have been driven by coastally-trapped Kelvin waves propagating down the west coast of Australia).  Sea-surface height anomalies associated with ENSO produced by employing an optimisation algorithm applied to the integration of the damped wave equations arising from the 1½ -layer model delivers a high correlation with the CESM1 model sea-surface height anomaly field and reveals some interesting findings relating to Rossby wave propagation across the entire basin.