Super Bowl LIX kicks off on Sunday. What number is that, though? Here's how to use Roman numerals and why the NFL uses them for the championship game.

Since early in the game’s history, the NFL has labeled almost every Super Bowl with a Roman numeral (more on that later) to designate where each matchup falls chronologically. But the numerals are more than just a stylistic choice — they’re actually used to provide a little clarity, according to the NFL.

Super Bowl 59, officially known as Super Bowl LIX, will kick off on Sunday night at 6:30 p.m. ET from New Orleans' Superdome. The use of Roman numerals in the event's name is a tradition that dates back more than fifty years.

It’s the thing that comes up every darn year: the number of the Super Bowl is written in Roman numerals, which is quite the tradition. But if you’re here, you might be wondering: how do you read Roman numerals in the first place?

The use of Roman numerals did not become an NFL tradition until Super Bowl V in 1971. The first two Super Bowls were known as the AFL-NFL world Championship Game. The name “Super Bowl” was officially adopted for the third annual game and the league retroactively added Roman numerals to the Super Bowls before 1971.

For nearly 60 years, the Super Bowl has become a central part of American culture well beyond the sphere of pro football. And for many, the Super Bowl also prompts the need to touch up on a certain other piece of culture that always re-enters the collective conscience around Super Bowl time.

The Arizona Cardinals started as the Chicago Cardinals in 1920 and won two NFL championships, but they haven’t won any Super Bowls. They haven’t been very c