When NBC lets us see victorious athletes from other countries, the Olympics medal ceremonies are one of the rare times — state visits, international athletic contests and a visit from the Toronto Blue Jays excepted — that we get to consider the national anthems of other nations.

Chances are you even have your favorites: “O Canada,” maybe, or “La Marseillaise.” But how much time have you spent thinking about them?

Sure, for “La Marseillaise,” you think of the stirring scene in “Casablanca” in which the patrons of Rick’s Cafe Americain rise up to drown out the hated Germans’ singing. But those lyrics — do you know they are singing, amid other sanguine images, about letting impure blood water the fields’ furrows? (Fortunately, the stanza about sons and women having their throats slit is no longer sung.)

The song emerged from the bloody French Revolution, so the lyrics make some sense in context. Or, as the Massachusetts musician and educator Nat Needle observes, “I would guess you’d have to be invaded and occupied a lot (and doing your share of invading and occupying) to come up with stuff like that and have it be appealing to people.”

National anthems came into vogue in the late 18th and 19th centuries. While some, like Japan’s, are based on songs or poems that are much older, that period was when most were adopted.

And here’s the thing: They all sound pretty much the same, when you think about it: Martial and often, like “The Star-Spangled Banner,” battle-born.

Robin Moore, a professor of ethnomusicology at the University of Texas, cites the work of scholar Thomas Turino on national anthems. “Turino’s argument is that nations are not trying to sound their differences but prove they have the proper trappings of European nations.” In other words, if you’re trying to prove you’re a nation of stature, you take the model of other nations of stature.

“I can’t think of a single place that has adopted their more unique local qualities into their national anthem,” says Moore. Thus no shakuhachi in the Japanese anthem, no sitar in the Indian one, no jazz in the American anthem.

Steven Greene, an associate professor of political science at North Carolina State University, is a bit of a national-anthem buff. “They’re a jingoistic vestige of a former era, but I love them anyway,” he says. So much so that when he goes to Carolina Hurricanes hockey games, he often picks games against Canadian teams so that he’ll get to sing along with “O Canada.”