Ashurnasirpal II was the first Assyrian ruler to place huge carved alabaster panels along the interior walls of a royal palace. They became a standard element of palace decoration throughout the Neo-Assyrian empire.

In the dimly lit chambers of the palace, color was used to enliven the carved images on the stone reliefs. Traces of black, white, red, and blue paint were visible when the reliefs were first uncovered; today all but blue still remains. Thick, black, probably bituminous paint colored the hair and beards of the figures; eyes were white with black pupils; and the tongues of bird-headed divinities were brilliant red. Black is preserved on the sandals of figures, occasionally with red for the soles and straps. Red also colors daggers and bows. The mud-brick walls above the reliefs were plastered and painted with floral, geometric, and figural designs in the same four colors.

The reliefs in The Metropolitan Museum of Art come from a number of rooms in the central portion of the Northwest Palace, where the state apartments were located. Single subjects were repeated many times around the walls of these rooms. Sometimes the subject was complete on one block of stone, as in Room 1. In other instances, two or more blocks formed a single unit of design, as with those from Room G, on which the king appears with attendants and divinities. In Room C, benevolent winged beings attended the sacred tree. These divinities and those with a bird's head were also placed in or beside doorways. Only in the rooms decorated with hunting and battle scenes did the subject matter take the form of a narrative around the walls, but there are no examples of these subjects from Nimrud in the Metropolitan Museum's collection.

The official rooms in the palace had specific functions. Room B, entered through doorways protected by colossal guardian figures, was the throne room. It contained reliefs with battle, hunting, and ritual scenes and had a large throne base. The centrally located Room G, which had particularly fine reliefs, was probably an important reception or audience hall leading to the open Courtyard Y. Room I, with its unusual stone floor slabs and wall niches, may have been a place for ceremonies requiring bathing and cleansing. The walls of some of the corridors and smaller storage rooms had limestone slabs with only the Standard Inscription carved across their surface.