Recent experiments have realized large Chern number quantum anomalous Hall insulators in nonmoiré rhombohedral multilayer graphene proximitized by ${\mathrm{WS}}_2/{\mathrm{WSe}}_2$. We exploit a minimal model based on intravalley ($u_a$), intervalley ($u_t$), and valley-exchange ($u_e$) components of the interaction to capture the emergence and competition of layer-polarized and quantum anomalous Hall phases in rhombohedral multilayer graphene. Using renormalization group analysis, we show that the layer-antiferromagnetic phase emerges as the leading instability, in good agreement with experimental observations. When $u_t$ dominates, the layer-valley-polarized phase with Chern number $\mathcal{C}=2N$ may become the leading instability, which awaits confirmation in future experiments. We then elucidate how the interplay between proximity-induced spin-orbit field and interactions triggers quantum anomalous Hall insulator with $\mathcal{C}=N$ at the critical phases of the transition from layer-antiferromagnetic phase or layer-valley-polarized phase to the layer-polarized insulator and further prove that the quantum anomalous Hall insulators are stabilized by the dominance of $u_a$ and $u_t$ over $u_e$. Our theory provides a concise understanding of recent experiments and offers insights to the realization of dissipationless topotronics using nonmoiré graphene.

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• Geometric & topological phases
• Phase transitions
• Quantum anomalous Hall effect
• Quantum spin Hall effect
• Renormalization group