Over 600 crew members, 500 extras, 80 horses, 65 stuntmen and -women and 4 separate camera crews were involved in the shooting of the Battle of Winterfell. A 26-acre field near Belfast that was set to be ploughed over was used, and a military advisor hired to rehearse the fights with the cast and extras, and drill and motivate them into action. At the time, it was the production's biggest and most ambitious battle ever crafted, and has been regarded as the greatest in the series by fans and critics alike.
The titular battle was a logistical feature practically unheard of in television history. Most hour-long television dramas take between 8 to 12 days to shoot, whereas the battle sequence alone took 25 days to shoot, including the parley scene and the aftermath. Based on the showrunners' initial rough description of the battle, director Miguel Sapochnik estimated that he would need at least 28 days; when he read their first script draft, he quickly amended the number to 42 days, while only 12 days had initially been budgeted. Subsequent re-writes scaled the schedule back to 25 days, of which the final three required an improvised script re-write when they ran out of time. These complications in the shooting schedule reportedly occurred because the battle was filmed in chronological order, to get the most natural performances from the cast.
Eighty real horses were used for filming the cavalry charges, without creating digital copies. The scene where Jon stands in the field as the Bolton cavalry darts towards him was accomplished practically - without the aid of any visual effects. Shallow canals were dug for them to run in so they would safely pass by each other, even though it looks like they almost collide into people and other horses. To make the fights even more realistically messy, dirt mixed with fake blood was constantly shot through the air. The tracking shot that follows Jon through the chaotic battlefield last an uninterrupted 60 seconds, although there may be invisible cuts when horses run closely past the camera.
This is the first TV show episode on IMDb to have over 100,000 user votes. The second was the following episode The Winds of Winter (2016), both with a 10.0 rating at the time.
Show-runners David Benioff and D.B. Weiss stated that after the episode aired, along with director Miguel Sapochnik, they monitored the IMDb score rather than professional reviews to gauge how well the episode was received.