  Experimental advances in the fabrication and characterization of few-layer
materials stacked at a relative twist of small angle have recently shown the
emergence of flat energy bands. As a consequence electron interactions become
relevant, providing inroads into the physics of strongly correlated
two-dimensional systems. Here, we demonstrate by combining large scale ab
initio simulations with numerically exact strong correlation approaches that an
effective one-dimensional system emerges upon stacking two twisted sheets of
GeSe, in marked contrast to all Moir\'e systems studied so far. This not only
allows to study the necessarily collective nature of excitations in one
dimension, but can also serve as a promising platform to scrutinize the
crossover from two to one dimension in a controlled setup by varying the twist
angle, which provides an intriguing benchmark with respect to theory. We thus
establish twisted bilayer GeSe as an intriguing inroad into the strongly
correlated physics of low-dimensional systems.
