Here is the full list of all 50 Game of Thrones achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Finish Alester's story
Finish the game without a single ally (except Mors and Alester) being KO'd
Finish Mors' Story
Finish chapter 15
Chapter 15: execute the judgement passed down on the Westfords
Finish chapter 14
Lose the final battle
Chapter 14: come to the aid of the Reapers
Complete all the secondary objectives of the story
Finish chapter 13
Chapter 13: reach Jeyne's room without ever being seen
Send 10 recruits to the Wall with Mors
Kill 400 enemies
Find all the statues of the Seven
Finish chapter 12
Chapter 12: take back Riverspring with a total victory
Finish chapter 11
Chapter 11: bring an end to the trial by combat in under 2 minutes
Finish chapter 10
Finish chapter 9
Chapter 9: suffer all the physical abuse during the torture sequence
Chapter 9: kill 6 of Lord Harlton's soldiers during the fight at dinner
Finish chapter 8
Seize the three objects of value from the Collector with Alester
Chapter 8: find the key in Alester's father's tomb
Emerge triumphant in the final arena combat
Convince Bethany to return to Chataya's brothel with Alester
Mete out 5 deathblows
Chapter 8: save Orys from the City Watch
Find 10 secrets with the vision of R'hllor
Finish chapter 7
Chapter 7: attack the camp without killing the sentries at the start
Chapter 7: find all the corrupt brothers of the Night's Watch
Finish chapter 6
Gain all the skills linked to R'hllor's fire with Alester
Chapter 6: don't lose pursuit of the bastard
Finish chapter 5
Gain all the skills linked to the dog with Mors
Reach the maximum level
Kill 10 enemies with Mors' dog in skinchanger mode
Learn all skills within a character's stance tree
Acquire 1 golden dragon
Finish chapter 4
Finish chapter 3
Use Mors' dog's sense of smell to find 5 secret objects
Finish chapter 2
Chapter 2: protect the people with Alester
Chapter 2: protect the nobility with Alester
Finish chapter 1
Chapter 1: confront the four recruits during the training session with Mors