The paper explores the concept of spontaneously broken (−1)-form U(1) symmetries in quantum field theories, extending the traditional understanding of symmetry breaking to a new class of symmetries. The authors define a (−1)-form U(1) global symmetry as one that can be coupled to a background axion field, which acts as a 0-form U(1) gauge field. They argue that this symmetry can be spontaneously broken, diagnosed by the dependence of the vacuum energy on a constant background field \(\theta\), as measured by the topological susceptibility. This leads to a reinterpretation of the Strong CP problem in QCD, suggesting that the problem arises from a spontaneously broken instantonic symmetry. The paper discusses known solutions to the Strong CP problem, such as the QCD axion and massless up quark, and explores new solutions that have not been previously considered. The authors also examine the behavior of gauge theories with spontaneously broken (−1)-form symmetries, including Maxwell theory in various dimensions and the Schwinger model, to illustrate the universal features of these symmetries. They find that the spontaneous breaking of the (−1)-form symmetry can lead to the emergence of a (d-1)-form Nambu-Goldstone gauge field, even if no propagating Nambu-Goldstone boson exists. The paper concludes with an outlook on further research directions.The paper explores the concept of spontaneously broken (−1)-form U(1) symmetries in quantum field theories, extending the traditional understanding of symmetry breaking to a new class of symmetries. The authors define a (−1)-form U(1) global symmetry as one that can be coupled to a background axion field, which acts as a 0-form U(1) gauge field. They argue that this symmetry can be spontaneously broken, diagnosed by the dependence of the vacuum energy on a constant background field \(\theta\), as measured by the topological susceptibility. This leads to a reinterpretation of the Strong CP problem in QCD, suggesting that the problem arises from a spontaneously broken instantonic symmetry. The paper discusses known solutions to the Strong CP problem, such as the QCD axion and massless up quark, and explores new solutions that have not been previously considered. The authors also examine the behavior of gauge theories with spontaneously broken (−1)-form symmetries, including Maxwell theory in various dimensions and the Schwinger model, to illustrate the universal features of these symmetries. They find that the spontaneous breaking of the (−1)-form symmetry can lead to the emergence of a (d-1)-form Nambu-Goldstone gauge field, even if no propagating Nambu-Goldstone boson exists. The paper concludes with an outlook on further research directions.