Don't listen to u/ryndaris on this. Because they didn't read Books 1-5, they don't even know what they missed. Thks makes it impossible for them to tell you it's fine to skip 5 whole books and go right to the last three. They have no clue as to how richly Books 1-5 inform all that happens in the rest of the series.

In Book 9 alone, there are nearly innumerable references to quotes and events in the earlier books that did not make it into the show, references that reward the readers, make the relationships and characters deeper, and make you feel more connected to the narrative and people.

Do not skip Books 1-5 even if you're coming from the show. Period.