system
Given the following post, respond as if you're commenting on Reddit:
human
[ASOIAF/GoT] Who grants the knighthood for the Knights of the Houses?

Further boiling it down, do the Lords of each house have the authority to grant the title to their own knights, or are they only acting as an extension of the King?  

A followup: If House Stark has the authority to grant knighthood to their own knights, does House Stark hold that authority over House Mormont and House Hornwood, or do the banner houses knight their own troops at their discretion?
gpt
Any knight can grant knighthood to anyone else. Typically it's granted to squires when they've proven worthy, but as we see with Ser Davos that's not the only way. As far as actual claim to title (lands, honors, etc) this can only be granted by a Nobleman, typically your King/Queen, Lord/Lady.


To your second question, Bannermen are lords as well as lieges, they can grant knighthood in their own right.