Katherine Hale tells Ava a joke about Bill and Hillary Clinton. Katherine is played by Arkansas native, Mary Steenburgen, who in her real life has been friendly with the Clintons since the early 1980s, when Bill Clinton was governor of Arkansas.
In Cottonmouth (2011) Boyd insists that the rest of his crew not bring their cell phones on a heist lest they accidentally trigger the explosives. A phone rings then with nothing happening. That was the setup for what happens to Lewis Mago here.
When Raylan and Art are talking about Markham and Grady Hale, Art mentions that the former US Attorney Simon Pool was killed at the corner of Limestone and Barr. On that corner in Lexington, Kentucky, is the United States Post Office and Court House.
Wynn Duffy reveals he grew up in Paia, a town of 2500 on the Hawaiian island of Maui. It is internationally known as "The World Capital of Windsurfing."