On its opening weekend in the United States, it went to number one, becoming the film to finally end the reign of James Cameron's Avatar (2009), which had sat at the top of the box office for seven consecutive weeks.
"Dear John" is slang for a breakup letter.
Amanda Seyfried wrote the song Savannah sings to John. Titled "Little House," the whole song is featured on the movie's soundtrack.
The Swedish flag flies over John's camp in Afghanistan. Director Lasse Hallström is a native of Sweden. The flag was put up by NATO and international cooperation in Afghanistan.