Breakthrough Hit: While Boy had minimal success on its release and spawning a minor hit with "I Will Follow" and October being regarded as a Sophomore Slump, U2's path to becoming the biggest band in the world and one of rock's most acclaimed bands truly started with this album.
Chart Displacement: Minor example, but while "New Year's Day" is the album's biggest international hit technically speaking, and is still a well-remembered song, but it doesn't quite reach the status as a classic of "Sunday Bloody Sunday", which wasn't released as a single at all in the UK and in the band's native Ireland (though it was a top 10 hit in Netherlands and in the US).
Reality Subtext: "Sunday Bloody Sunday" and much of the rest of the album was a response to The Troubles, which was still an active conflict at the time the album was made.
The original US CD release in 1985 was the only one in Island Records' discography to use the "target" label design characteristic of Warner Music Group releases in the first half of the '80s. Because of this, it is also the only target CD to use the green-on-purple color scheme that Island picked; another, much rarer target CD reused WEA's purple-on-teal design.