More even than the masterwork of "the Shakespeare of Painters," Rembrandt's The Night Watch is a Dutch national treasure, depicting the citizen soldiers of the unique Dutch Republic that thrived during an era of absolute monarchies in Europe. However, there is a crucial detail in the painting that has been ignored in previous interpretations, and an explanation of that detail could add another layer of meaning. (At the Rijks Museum website you can examine the painting almost as well as if you stood in front of it.)
Captain Frans Banning Cocq, in black with a red sash, at the spatial center and the farthest forward, is not looking in the direction he is pointing. He is gesturing straight ahead, at the viewer, but looking off to the side. Why? What has suddenly caught Banning Cocq's attention? Could it be the enemy? Could this be the first instant of the captain noticing the enemy in the distance? If so, there has not even been time enough for an emotion to register.
The presence of the enemy may be confirmed by the most mysterious figure in the painting, the spot lit girl. (She could be a child version of Rembrandt's wife, Saskia, who was dying, probably of tuberculosis, while he was finishing this.) Only the girl has the same line of sight as Banning Cocq, and she is frightened (and fascinated, as a spirited child would be) and fleeing. She and Banning Cocq are visually linked by that long diagonal line that starts with a pike that descends toward and ends close to the side of Banning Cocq's head, and then by inference the diagonal line continues from Banning Cocq to the girl.
A goateed young man in a glinting helmet, behind, above, and to the left of Banning Cocq, seems also to see the enemy, though it's not completely clear. Everyone else is oblivious to the enemy.
Nobody today is sure just what this militia unit is doing. Speculation includes joining a parade or joining a shooting competition. To get their permission to depart from the traditional Dutch group portrait, could Rembrandt have promised action in battle? And could he have inserted a satiric subtext in which the enemy surprises them?
Being oblivious to a threat can have a comic aspect inside the theater of the frame and there are several comic aspects to this painting; such as, the accidental discharge of a musket, pointed harmlessly into the air, by a diminutive helmeted figure immediately behind Banning Cocq. This is slapstick, and for plausible deniability with customers expecting heroism, Rembrandt puts the powder plume behind the feather plume on the hat of Lieutenant Willem van Ruytenburgh, in yellowish white. But the protective hand held-up by the man immediately behind and between Banning Cocq and Ruytenburgh makes clear that the musket is firing. It is the split second before anyone, except the man with his hand up, has reacted to the discharge. The musket is firing simultaneously with Banning Cocq's first sighting of the enemy.
This painting also has the wry touch of an eye, under Rembrandt's characteristic beret, peeking over the right shoulder of that same goateed young man in the glinting helmet who seems to see the enemy. That eye is at the exact center of the canvas as it was before being cropped.
If Rembrandt is subtlely satirizing wealthy poseurs, like that fop transfixed by his banner directly above the girl, or even Banning Cocq and Ruytenburgh, still the rest of this militia unit looks formidable, composed mostly of capable-looking men. The enemy may have surprised them but that does not mean they can't beat him. Two of the musketeers (who may have seen the enemy before their commander), one to the left of the girl and another behind Ruytenburgh, are within seconds of being ready to fire.
I'm just a layman in love who noticed all this during a recent stay in Amsterdam. In the vast literature about Rembrandt, others must have mentioned this before, though I have yet to find anyone. I did contact three of the top Rembrandt scholars. This interpretation was new to all of them, none dismissed it out-of-hand though two expressed objections.