Yes, this subject brought out all the nuts.
BACKGROUND: Over the years, a number of Viking era graves were found with swords.  The base assumption was that these were all males, and military.  A lot of us always insisted this was a false assumption. Swords were often a mark of rank and wealth (and still are). It meant the interred was of status, not necessarily a warrior. 
Then, some DNA tests showed a lot of them were actually female.
This is where the screeching harpies came in with their popular conspiracy that there were literally thousands of women in this and every generation who were doing the things men did, and then somehow erased from history so no one would ever know, over and over. This is of course, ridiculous on several levels.
Then the small-dicks got into it because obviously, no woman ever measured up, so the females had swords as marks of rank, but the men were still probably warriors.
So here's the problem with that:  If the sword is the mark of a martial person, you don't present it to a non-martial person, except to honor them for something martial. (Much like the US has civilian and military decorations, and civilians can't earn the military ones, except for a rare handful like the Civilian Defenders of Bataan and Corregidor, who fought as combatants because there was no choice).
Once again, as a lot of us said, those swords were badges of rank, and may or may not indicate the owner was ever part of the military caste, or ever fought.
The Sagas and other documents record a small number of women fighting as combatants in the Viking Era. Let's go through them one at a time:
When Leif Erikson's pregnant half-sister Freydís Eiríksdóttir was in Vinland, she is reported to have taken up a sword, and, bare-breasted, scared away the attacking Skrælings.[6] The fight is recounted in the Greenland saga.
So, this woman fought in extremis.  NOTE: She had enough familiarity with a sword to reach for it rather than some other weapon, apparently confident she could use it to some effect, and said sword was available where she could readily reach it.  This implies at least some basic familiarization in case of emergency. And that it's documented this way shows no negative or questionable perception around her doing so.
Before that, we find:
Saxo Grammaticus reported that shieldmaidens fought on the side of the Danes at the Battle of Brávellir in the year 750:
Now out of the town of Sle, under the captains Hetha (Heid) and Wisna, with Hakon Cut-cheek came Tummi the Sailmaker. On these captains, who had the bodies of women, nature bestowed the souls of men. Webiorg was also inspired with the same spirit, and was attended by Bo (Bui) Bramason and Brat the Jute, thirsting for war.
These women are presented as unusual. Notice they had "The souls of men." To engage in martial activities, they couldn't be "women" in the context of the culture. That's important, and we'll come back to that.
But in context, they're presented positively. It's not "The Danes were such wimps even their women led them into battle."  It's "Holy crap, the Danes even had two women who were worthy."
The Byzantine historian John Skylitzes records that women fought in battle when Sviatoslav I of Kiev attacked the Byzantines in Bulgaria in 971. When the Varangians (not to be confused with the Byzantine Varangian Guard) had suffered a devastating defeat in the Siege of Dorostolon, the victors were stunned at discovering armed women among the fallen warriors.
This battle was rather one-sided. The Rus (related to the Vikings) got slaughtered. Once again, the women fought because they had to; they were going to die anyway. They armored up as the men, went out, and presumably had at least minimal training to make them more than meat shields. How much more we don't know.
Nor would the Byzantines be inclined to lie and claim they were fighting women if they weren't. It's not manly.
The Rus clearly accepted the idea and did the best with it.
Lagertha's tale is recorded in passages in the ninth book of the Gesta Danorum, a twelfth-century work of Danish history by Saxo Grammaticus. According to the Gesta (┬╢ 9.4.1ΓÇô9.4.11), Lagertha's career as a warrior began when Fr├╕, king of Sweden, invaded Norway and killed the Norwegian king Siward. Fr├╕ put the women of the dead king's family into a brothel for public humiliation. Hearing of this, Ragnar Lodbrok came with an army to avenge his grandfather Siward. Many of the women Fr├╕ had ordered abused dressed themselves in men's clothing and fought on Ragnar's side. Chief among them, and key to Ragnar's victory, was Lagertha. Saxo recounts:
Ladgerda, a skilled Amazon, who, though a maiden, had the courage of a man, and fought in front among the bravest with her hair loose over her shoulders. All-marvelled at her matchless deeds, for her locks flying down her back betrayed that she was a woman.
Impressed with her courage, Ragnar courted her from afar. Lagertha feigned interest and Ragnar arrived to seek her hand, bidding his companions wait in the Gaular valley. He was set upon by a bear and a great hound which Lagertha had guarding her home, but killed the bear with his spear and choked the hound to death. Thus he won the hand of Lagertha in marriage. According to Saxo, Ragnar had a son with her, Fridleif, as well as two daughters, whose names are not recorded.
So, once again, she fought because she had to, as did the other women.
Now, this may be partly fictionalized, so we go to context:
The women are held in respect for assisting in their own rescue.
The purposed of enbrotheling them was humiliation, not disgrace--it was to bring them down, not to imply shame to their families (other than by not being able to protect them). Quite a few cultures would shun or even execute those women for having been raped. In this case, despite that, at least one was considered worthy enough to be sought as a wife of status. Nor was it unmanly to marry a woman who fought. It was a positive.
(In Grammaticus's accounts, "dressed in men's clothing" means suitable garb for fighting--pants, tunics, possibly armor.)
So now we come to a recent, fully documented instance:
http://onlinelibrary.wiley.com/doi/10.1002/ajpa.23308/full
So, this burial does contain a sword. It also contains an ax, a large langseax that is purely a weapon, not a tool, a two handed axe, a spear, two shields, bodkin tipped arrows, stirrups and two entire horses.
It was first called a male warrior's grave.  Then someone observed the pelvis was probably female. Then it was genetically proven the occupant was female.
Then all of a sudden it wasn't a warrior's grave at all.
Within seconds of me posting this link on my wall, one individual had a complete, screaming, online meltdown. I strongly suspect he actually crapped his pants.
He loudly insisted it couldn't be a warriors grave because no culture ever had female warriors, and posted a link that debunked the feminist claim that half the burials in York were female because they contained swords. This is true. It's also not relevant to this find.
Then he went on to insist that the sagas are just fiction and not relevant, and grave goods don't prove anything and are not relevant, and it was something other than a warrior's grave because it had a female in it and there were no female warriors, and I obviously knew nothing of history.
So, point by point:
"The sagas are fiction and speak of ridiculous fantasies."
True. They also speak to the culture, and we have references above to females fighting in exigent circumstances. They're not foils, comedy relief, or sex objects. They're warriors. That perception is culturally relevant. Also, based on a third hand retelling of Beowulf (not a saga per se), we have found what are probably Heorot and Beowulf's barrow, right where they were described.  We have the same with the Bible, and with Tlingit accounts from the Pacific Northwest of the tsunami that hit about 1700. A saga alone is not evidence, but you can't throw them out entirely. And if you do, you can't also decide to keep them relevant for male history.  This is not only toxic masculinity. This is a dickless little bitch who's terrified of women.
"Grave goods don't prove anything."
Odd. Apparently they did when the grave was "known" to be male. Also, wrong.  If we find valuables in a grave, it's probably not a peasant. If we find a needle case, shears, keys and tweezers, it's probably a female grave. If we find copious weapons, it's probably a warrior's grave. Note "Probably." Not proven, but if you find those female accoutrements, a comb, brooches, etc, you don't assume it's a male ruler. If you find gold, weapons, valuables, you don't assume it's a beggar.
We had this same crap years ago, by the way, when some smal number of the Pharaohs were shown to be women. They were just "Queens buried in Pharaohic context."
"It can't be a warrior's grave because it has a female in it and there were no female warriors."
Circular logic. Once you've defined your circle, nothing can get in or out.
I asked him what type of grave it was if not a warrior's grave. His response: first to claim he didn't need to answer because I'd been rude back to him, therefore "showing my colors." Which of course is an evasion. Then to say it was "some other type of grave of status, but not a warrior's grave" again. He was unable to suggest what type of grave might be full of martial goods but not martial in nature.
I blocked the limp-dicked little shit because he was making rational discussion impossible.
At this point, Dipshit Number Two entered the fray and said, "Even if it was a martial grave, there's no evidence she ever stood in a shield wall, so she's not a warrior."
Wow. Those are some supercharged V8 equipped goalposts there.  No one ever claimed she engaged in any particular act in any particular battle. We don't know. Nor do you, so you can't state a negative either.
My last Army commander was a general who'd never been in combat.  He was still part of the military caste.
Now, we don't have proof the female occupant of this grave ever stuck a spear in someone. This is true. But the grave is a martial grave--multiple weapons, stirrups, which were typically used in martial context. One didn't ride pet or draft horses at speeds that would necessitate them for several reasons. And we have two horses, and a grave the size of a small house, in a military context in a large town. The weapons have not been ritually "killed" to prevent theft. There was no expectation this grave was going to get robbed. This means it was guarded and in an established cemetery.
There are numerous weapons of a working nature. A person of status might wear a sword to court, to council or to diplomatic functions, but if you show up with a skeggox and langseax as well, you aren't there to look pretty. You're there to take someone's head off. These weapons were not tokens.
So in this context, if your culture is so stiff-cocked and manly that women can't ever be warriors (and extant evidence is it was not), you would not EVER put a woman in a grave with martial implements. You'd be disgracing said implements. Would the Arabs do this? Of course not. Just as civilians can't get military medals in our culture. There are civilian medals the President can award them. They don't get ours. Only the military, and only certain segments of the military, can get certain awards and certifications. A civilian might be a complete badass, but he is not a Soldier/Sailor/Marine/Airman. The contextually relevant reference above is the Civilian Defenders of Bataan and Corregidor, and a few others, who actually fought with the military in such a fashion and under such circumstances that we said, "You are now of us." They became warriors.
This female is buried in what was always understood to be a martial grave.  End of discussion.
Now, there are varying reasons as to why. She could have been a legit hands-on warrior herself. The evidence is she was in fact a "maiden" as far as marriage went (height, undamaged hips, no partner buried with her, her horses--probably her most trusted and valuable animals--buried with her and not willed to someone). All those make possible that she did in fact kick some Norwegian or Balt ass.
It could be she was the swiftest messenger around, though the fighting axe argues against that.
It could be she was the horse trainer for that element. An important, martial position. But again, the axe isn't quite correct. A spear would be better.
Possibly she was the local countess who donated land and money. This could make her an honorary member of the caste. Though there's no male precedent for this I'm aware of, so it's unlikely.
She might have taken up a male relative's position for vengeance--respected in those cultures and even noted in literature.
She could have been some sort of management or tactical whiz who could outsmart the enemy, though that would still argue for presence on the battlefield, which, even if there's "no evidence she ever stood in a shield wall" (we have no such evidence for anyone that I'm aware of), makes her a warrior.
Without either some attestation, a burial marker, or other evidence, we cannot prove positively which of those she was.  But it is certain that this woman was buried in a martial context by a martial culture, which means they considered her martially relevant enough to dig a hole the size of a small house, put her, her horses, and (adjusted dollars) about $30,000 worth of weapons and accoutrements in with her. And to not put in a single female accoutrement. She was not buried as a woman. She was buried as a warrior.
We have a single confirmed find of a Viking Era woman buried in martial context. This does not mean there were thousands of others. Nor does it mean there were none.