For millennia humans have gazed into the sky and wondered where it all came from. Today, using cutting-edge supercomputer and telescope technology, numerical cosmologists are assembling a scientifically-based origins story of the Universe. Central to this is understanding the formation and evolution of galaxies, which are the primary markers by which we map out the cosmos. South Africa’s MeerKAT radio telescope, the largest scientific project ever undertaken by the DST, has elevated South Africa to a global player in this quest by adding the world’s most advanced interferometric radio array capable of detecting gas and black holes in galaxies over the majority of cosmic time. I am involved in several MeerKAT Key Projects for which I develop and employ cosmological simulations of galaxy formation to help contextualise and connect MeerKAT’s radio observations with other multi-wavelength data from the X-rays to the infrared, and to guide future observations towards optimally advancing the most important gaps in our knowledge. This project will employ my group’s state-of-the-art Simba simulations to elucidate what MeerKAT data tells us about some key mysteries of galaxy evolution, such as the role of supermassive black holes and tenuous atomic hydrogen in shaping the Universe we see.