Depends.
The sagas and poem in which they appear conflict. Their number seems to be 27, with one of them the chief Valkyrie being the worst of the lot. Some poems make them out to be horrible, foul mouthed, blood soaked, lascivious harpies, while others have a less violent aspect about them. They are more restrained sympathetic creatures.
They carried shield and spear, but had no need of armor, being mortal. That was more for Victorian Modesty when these people began to trapse around the operatic stage.
Theologically or mystically they are even more obscure and are connected originally in some way with the post shammenistic lore of the ancient Germans heavily connected itself with trees, animals and mythical races like elves, dwarves and giants. The self-refashioning trick of the giant Fafnir with the aid of the tarnhelm in Wagnerian fantasy turning himself into a dragon is a remote indication both ot the interchangeability of form with these creatures who were emminatnions of nature and an indication that the Gods and the Valkyries might also be only indeterminate identities and not fixed personalities like the Greek Gods (though in the early Greek religion they too were connected with creatures and happenstances as well.
UNFORTUNATELY,-- no HIGHLY UNFORTUNATELY-- the phantasmagorica of Ricard Wagner has come down to us as the picture of the old Germanic Gods and that's not a really good picture. Perhaps the most adulterated version possible but also the most absurd, as Wagner himself knew only a few of the names of the Germanic Gods. Significantly the common conception of the Valkyrie as a huge beefy woman in odd bits of ironmongery and horned helmet would have been laughed off the stage, no thrown off bodily by Wagner. Brunhilde's in Wagner's idea were lithe, athletic yourn girls with a tremendous voice who literally could do acrobatics on stage while singing. Think of a blonde Angie Harmon who was a world class gymnast with a voice like Aida. The character you most see and exemplified by the two figures on the left is a Brigitte Nielson carrying all the armor the prop room had. In reality it was more like a Risi Stevens in the 80's Bayreuth version. Remember Shield maidens don't need armor they're immortal, only a diaphanous shift for modesty's sake.
The fame of the Valkyries is due pretty much entirely to the rousing Music Wagner wrote for these cheerleaders of the "Strength Through Joy" movement and which has come down to us as a sort of "Luftwaffe Lullabye" Compared to them the far more intriguing air headed beach babes, the Rhinemaidens come off as completely boring.
