Baduhenna, the Dutch Goddess of battle and the forest. I already knew of a possible connection with Badb, one of the Morrígna, due to the etymology of both their names. The root badw- or badv-, meaning battle, that they both share.
Donahue, in his article “the Valkyries and the Irish War-Goddesses” exposes perhaps a deeper link. He states that it is likely that the Scandinavian and Germanic Valkyrie and the Irish Wargoddesses evolved together. That is to say that because of the close relations between the Celts, the Gauls and the Germanic people it is likely that these cultures intermingled, and through that their mythology and beliefs were influenced. The Valkyrie for example, went from demons, “those who bring fear”, to beautiful, almost Goddess-like, women who chose the slain and poured mead in the Halls of Valhalla.
De Vries, in his article “studiën over Germaanse mythologie” also speaks of the links between Valkyrie, the matronae (triads of Goddesses commonly worshipped by the Germanic tribes), the Norns, the dísir, and the Goddess triad that is the Morrigan.
Next to Badb and the Valkyries, there is another Goddess to consider. The Gaulic Goddess Cathubodua, whose name means “battle-crow”. Perhaps Her link with Badh is even a stronger one, with the crow aspect being right there in the name. All we have of Cathubodua is the inscription of the name upon a shield, unfortunately not a lot to go on.
Baduhenna might not have the crow in Her name, but she does have something else. Her “mythology”. I’m putting “mythology” in quotation marks here, because it is not myth, it is history. However the history only tells us that there was a battle, that the Frisians against all odds attempted to overthrow the tyrannical Roman leader, that they won that battle and killed 900 Romans, and that the retreating Romans were so paranoid, that they slayed 400 of their own men. Those are the facts. But if we look at it in another way, a different story can perhaps be told: a small group of people won a battle against a far greater and better trained army. This battle was fought in a sacred forest, dedicated to their Goddess; a Goddess of war. Divine intervention perhaps, the Goddess choosing which side of the conflict will be the victor, and which will be slain. Much like both the Valkyrie and the Morrigan. The remaining soldiers fleeing, but being so overcome with confusion and madness that they turn on their own battle-brothers. Just like the madness that Badb spreads when she flies over the battlefields in her form as a crow. Which is why Braakman is his article “Baduhenna. Godin van het Slagveld.” states that Baduhenna and Badb are one and the same, and says: “Baduhenna had struck again.”
So we have a Gaulish Battlegoddess, the Valkyries, and the Morrigan. So where does Baduhenna fit into this? Perhaps nowhere, for as far as we know She is not part of a triad or group, like the Morrigan and the Valkyrie. But to me, they do have a connection. To me, the theory that the Valkyrie and the Irish-, Gaulic-, and Germanic Goddesses of War and Battle influenced each other, and therefore, grew together, seems very logical. I tend to see them as sisters, or cousins. Not the same, but part of the same family.
For me personally, the link with the Morrigan is stronger, simply because of Baduhenna’s “mythology”. This is also the reason I relate crows with Baduhenna, without there being evidence for it. And perhaps also because Morrigan was already a known Goddess to me, through my partner who considered Her his patron for a while. I always felt drawn to the Morrigan as well, but it never felt right, not completely. And who knows, perhaps this was because She was trying to point me towards Her Dutch sister all along.
 Donahue, C. (1941). The Valkyries and the Irish War-Goddesses. PMLA,56(1), 1-12. doi:10.2307/458935
 de Vries, Jan P.M.L. (1931). Studiën over Germaanse mythologie. Tijdschrift voor Nederlandse Taal en Letterkunde, 50, 85-125. Link.
 Braakman, W.A. (2001). Baduhenna. Godin van het Slagveld. Westerheem. Tijdschrift voor de Nederlandse Archeologie, 50(1), 2-12.