Why does Craster marry his daughters?

[Kandrax]

1 minute ago, Frey Kings said:

Human Scarifies are a common thing. The gods demand it. 

I don't remember that other wildings sacrifice humans.

[John Suburbs]

19 hours ago, JNR said:

But none of the rangers have noticed or reported sentient ice demons that closely resemble Others from ancient myths (except that they're prepared to parley in a peaceable manner to achieve diplomatic ends). 

Nobody is reporting this because nobody is living to tell the tale:

Quote

Jeor: "Do you think your uncle Benjen was the only ranger we've lost this past year?"

Jon: "No." There had been others. Too many.

Apparently, the only ranger to survive an encounter with the Others was Gared, and Ned cut his head off thinking he was a raving loony.

 

19 hours ago, JNR said:

And yet Craster has obviously spent decades doing the same things we find him doing in books 2 and 3.... because he is literally the only male human being at his keep -- one man, not a young one, among many women of varying ages.

Do we know it's been decades? And if he's been sacrificing for this long, do we know the Others have been taking them and not some scavenger?

 

[Lord Varys]

1 hour ago, John Suburbs said:

Nobody is reporting this because nobody is living to tell the tale:

Apparently, the only ranger to survive an encounter with the Others was Gared, and Ned cut his head off thinking he was a raving loony.

That is an important point. And it is not unlikely at all that, say, Bloodraven was ambushed by Others and/or wights and then saved by Children of the Forest or their associates (Coldhands; his own predecessor as greenseer) when he disappeared into that cave.

We have no reason to believe the Others have been dormant or away until the Prologue of the first book or a few years before that. They could have made their first quiet moves decades or even centuries before the series began.

And in fact - we still don't have confirmation that they were ever gone. They could have just up there in the Heart of Winter, always watching, always conscious, waiting until the time was right.

1 hour ago, John Suburbs said:

Do we know it's been decades? And if he's been sacrificing for this long, do we know the Others have been taking them and not some scavenger?

We have no reason to assume Craster ever made common human sacrifices - out in the woods at some altar, or in some kind of ritual at his keep.

He could have literally handed over his children to the Others. Either at some meeting place in the forest or at his keep when the Others came for visit and a talk - just as Jahwe used to visit Abraham.

The way he talks about his gods indicates he doesn't only believe they exist and that they help him. He has proof that they are the real deal and that they can make a difference.

A man like Craster also appears to be far too cynical to just start some weirdo ritual in the (empty) hope that some gods help him. He is the son of a crow, he has a larger picture of the world than the average wildling.

Sons are basically his guarantee that he himself and his women are safe when he grows feeble in old age, yet he still doesn't have sons of his own. That he doesn't have as much as he has daughters is pretty understandable - too many could become a danger to him. But there is also the opportunity of simply driving them away - or encourage them to make a living elsewhere.

Sons are also worth much more than daughters in this society, so it is very odd that Craster would keep his daughters and sacrifice his sons - unless there is a very good reason that he does that. If superstition and mere weirdo religious belief would motivate his actions he would most likely start with the women he doesn't need - old ones, babies, etc. - and turn only to more valuable members of his family when the situation becomes really dire.

Instead, he sacrifices only the most valuable members of his family, and keeps the women only to produce more sons to sacrifice. Would he not be under constant pressure to satisfy the needs of the Others he would most likely not keep as large a harem as he has. 

[Bowen 747]

Marriage is not the important matter with Craster.  Craster uses his sons to pay his rent to the WW so he can live as a free man on their side of the wall. 

[JNR]

5 hours ago, John Suburbs said:

Nobody is reporting this because nobody is living to tell the tale

I'm again going to point out that if

1) Craster is keeping his own keep and the people there safe through sacrifice, and

2) The free folk aren't doing Craster's routine en masse... then

3) All the free folk except Craster's people should have been killed by now

This, I am confident, the Watch would have noticed.  They haven't, because it never happened.

5 hours ago, John Suburbs said:

Do we know it's been decades? And if he's been sacrificing for this long, do we know the Others have been taking them and not some scavenger?

Decades certainly seems likely given that there are multiple generations of wives and many of them in total, and zero male descendants present. 

We certainly do not know that Others have been taking the babies.  Such a thing never happens in canon, nor does anyone report having seen it.

Here's a subtler point. 

Notice that Lord Commander Jon Snow charters his best friend, the learned Sam, to report all he can on the Others.  This is a critically important topic, essential to the defense of the realms of men, which Jon and Sam are, of course, sworn to protect.

And Sam... though he was standing right there when Craster's "wife on the left" reports the Others are Craster's sons... doesn't consider this tidbit worth mentioning.

He could, in other words, notify Jon of the source of the Others -- they come from Craster's wives' uteruses -- but, quite noticeably, he doesn't bother. 

Sam's a bright boy.