Quantum magnetic materials provide analogues of quantum field theories, but allow for behaviors impossible for ordinary particles, making them useful for both technology and fundamental research. In this talk I introduce quantum magnetic materials and neutron scattering as an informative probe of their behavior. I then discuss three examples of how neutron scattering reveals important details of quantum magnetic materials: (a) detecting magnon quasiparticles in
elemental Gd, (b) detecting quantum entanglement via entanglement witnesses in spin chain KCuF3 and 2D triangular lattice KYbSe2, and (c) measuring real space dynamics to study quasiparticle and collective quantum behavior.