We present a new determination of the evolving galaxy ultraviolet (UV) luminosity function (LF) over the redshift range using a combination of several major Cycle-1 JWST imaging programmes – Public Release IMaging for Extragalactic Research, JWST Advanced Deep Extragalactic Survey, and Next Generation Deep Extragalactic Exploratory Public Survey. This multifield approach yields a total of arcmin² of JWST/NIRCam imaging, reaching (5-) depths of AB mag in the deepest regions. We select a sample of 2548 galaxies with a significant probability of lying at high redshift () to undertake a statistical calculation of the UV LF. Our new measurements span  mag in UV luminosity at , placing new constraints on both the shape and evolution of the LF at early times. Our measurements yield a new estimate of the early evolution of cosmic star-formation rate density () confirming the gradual decline deduced from early JWST studies, at least out to . Finally we show that the observed early evolution of the galaxy UV LF (and ) can be reproduced in a cold dark matter Universe, with no change in dust properties or star-formation efficiency required out to . Instead, a progressive trend towards younger stellar population ages can reproduce the observations, and the typical ages required at 8, 9, 10, and 11 all converge on  Myr after the big bang, indicative of a rapid emergence of early galaxies at . This is consistent with the first indications of a steeper drop-off in we find beyond , possibly reflecting the rapid evolution of the halo mass function at earlier times.