He accepted a boring job and became a member of 'the Establishment'.
His novels were disliked by 'the' literary 'establishment'.
the 'establishment' of a business/school/church/settlement
(..) The Maiden... where is the Maiden? And the Stranger. - Two is extra, you realize... - Yes, yes. What are you doing? This establishment belong to Lord Petyr Baelish. You can't... You have profaned our Faith. The Faith of our fathers and forefathers. I am the High Septon of the... You are a sinner. (..)2015 TvShow: Game of Thrones Title: High Sparrow Season: 5 Episode 3