The phenomenon of frustration greatly enriches the accessible physics of quantum magnets. With this in mind, we study the magnetism of ${\mathrm{NdCl}}_3$ using a combination of bulk property measurements and neutron scattering techniques. The low-temperature heat capacity reveals two magnetic transitions at $T_{N1}$ = 270 mK and $T_{N2}$ = 180 mK. However, much of the magnetic entropy is released above $T_{N1}$, manifesting as a broad peak centered at $T^{*}\approx$ 450 mK. A similar broad peak is observed in the magnetic susceptibility, which possesses a clear anisotropy; these data can be well fit using a one-dimensional XXZ model, yielding an antiferromagnetic nearest-neighbor exchange $J_{\mathrm{NN}}$ = –0.962(2) K and exchange anisotropy close to the Ising limit. Single-crystal elastic neutron scattering reveals highly anisotropic magnetic diffuse scattering above $T_{N1}$, confirming that quasi-one-dimensional, short-range, antiferromagnetic order is the origin of the broad peak in the heat capacity and magnetic susceptibility. Magnetic Bragg peaks characterized by a $\vec{k}$ = (0 0 $\frac{1}{2}$) propagation vector emerge below $T_{N1}$. Interestingly, the magnetic diffuse scattering persists for $T_{N2}<T<T_{N1}$, indicating a regime of coexisting short- and long-range order. The magnetic Bragg peaks exhibit an additional increase in intensity below $T_{N2}$ with no change in $\vec{k}$. Concomitantly, the diffuse scattering disappears, indicating the attainment of full long-range order. While the precise nature of the ordered magnetic ground state remains unresolved, the observed magnetic scattering indicates predominant $c$-axis moments with a small $ab$-plane component. We propose that the quasi-one-dimensional behavior and the coexistence of short- and long-range order are driven by frustration of exchange interactions with significant anisotropy.

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• Frustrated magnetism
• Magnetic order
• Magnetic phase transitions
• Neutron scattering