India-Asia collision represents one of the most dramatic Cenozoic tectonic events on Earth. Both the dynamic origin and collisional process of this event remain debated. We circumvent these questions through quantitative geodynamic modeling that attempts to satisfy multiple observational constraints.  Here, I will introduce some preliminary results along these efforts. For example, we evaluate the driving mechanism of the collision through global subduction models with data assimilation by simultaneously matching the Cenozoic plate motion history, present mantle seismic structure, and force balance of the India-Tibet system. We elucidate the nature of the subducted Greater Indian plate through matching the crustal volume of Himalaya, the spatial-temporal tectonic records within Tibet and its present-day lithospheric architecture. We also attempt to constrain the timing and style of the collisional process through matching the rotation history of the incoming Indian plate.