Francis looks at a yardage book, a series of hand-drawn diagrams of every hole at The Country Club. Yardage books did not come into use until the 1960s, first by Deane Beman, later popularized by Jack Nicklaus.
Harry Vardon is credited with inventing the "Vardon" grip, which involves the fingers of the hands overlapping. During the golf scenes, Vardon and Ouimet were using the "interlocking" golf grip, the opposite of the "Vardon" grip.
Going into the fourth round of the 1913 U.S. Open, Ouimet trails Vardon and Ray by one stroke. However, the final leader board shows all 3 shooting 79, with a total of 304 strokes for the tournament. That means all 3 were tied entering the fourth round.
During the playoff, Harry Vardon's ball blocks Francis Ouimet's ball's path on the green, a play called a "stymie." That only applied to singles match play. The playoff for the 1913 US Open was medal (stroke) play, and the stymie rule would not have applied. This USGA eliminated the rule in 1952.
The 17th hole of The Country Club is shown as a dogleg right, and Harry hits his ball into an unseen trap on the right side of the corner of the dogleg. In 1913, The Country Club's 17th hole was a dogleg left, and Vardon hit his ball into a trap on the left side of the fairway.
On the 18th green, Vardon misses his first putt, then holes out. While this is common in present-day golf etiquette, Vardon would have been penalized in 1913. The player who is farthest from the hole plays first.
The opening shot begins with a scene set in Jersey, overlaid with the caption "Isle of Jersey, England". Jersey is one of the Channel Islands, and the main island of the Bailiwick of Jersey. It's a British Crown Dependency with its own administration. The Queen of England is the head of state in her capacity as the Duke of Normandy. It's closer to France than to England, and is neither geographically nor administratively part of England.
In the playoff round, a quick pan across the 3-player scoreboard shows Ouimet and Vardon tied at Even. Below their score is Ted Ray at +6. When the pan is reversed frame-by-frame, Ray is really only at +3..