Most galaxies, if not all, appear to host central super massive black hol es, whose masses correlate with host galaxy properties. This suggests that the growt hand assembly of galaxies is coupled to that of their nuclear black holes. Wehave developed new, more empirically driven semi-analytic models to trackblack hole growth that explores a range of initial seeding models, as well as accretion modes. New insights into the formation, fueling and feedback from black holes inthese models will be presented. We show that our understanding of the assembly history of black holes stands to be transformed, withupcoming and future observational probes JWST, LYNXand LISA that will provide key discrimination between these models, and further illuminate the blackhole-host galaxy connection.