It has been a decade since the discovery of high-energy cosmic neutrinos, and new information has also been brought from electromagnetic and cosmic-ray observations. The field of high-energy multimessenger astrophysics is rapidly evolving, and we may start to find clues to the origins of high-energy cosmic neutrinos. I will highlight our recent developments about the sources of high-energy astroparticles, and discuss some implications for non-thermal processes in extreme environments and physics beyond the Standard Model.