Title: Chiral anomaly in curved backgrounds Abstract: Anomalies in quantum field theory stem from the broken symmetry of the classical theory upon quantization. A prominent example is the chiral anomaly related to fermionic fields and to the Dirac operator. The chiral anomaly can be seen arising from the topology of the problem setting and analyzed by applying the Atiyah-Singer index theorem on the Dirac operator. This has been well-studied in a locally Euclidean framework, but rigorous generalizations to curved geometries are lacking. In this talk I will briefly cover some basics of quantum anomalies focusing on the chiral anomaly and the Riemannian Dirac operator, and outline a generalization of the Riemannian case based on the index theorem on spatially compact Lorentzian manifolds as recently introduced by Bär & Strohmaier (arXiv:1508.05345).