“As far as we know, there were no Croatians in the American Revolution,” Marko Zlatich says. “Too bad.”

Too bad, Marko means, because he’s of Croatian descent and he studies the American Revolution. If Marko could trace his lineage back to an officer who served in the Revolution — through the stringent rules of primogeniture, one eldest son at a time — he would be eligible for membership in the exclusive Society of the Cincinnati.

And that would be kind of neat, because every Thursday that’s where you’ll find Marko: in the library of Anderson House, the Massachusetts Avenue NW mansion that is the society’s headquarters, his laptop and papers spread out around him.

Marko, 81, is a retired World Bank records manager and archivist, and he brings an archivist’s attention to detail to his lifelong quest: to understand what exactly the soldiers who kicked the British out of America nearly 240 years ago wore when they were doing the kicking.

Marko is obsessed with uniforms.

Marko Zlatich researches the history of the uniforms worn by American soldiers during the Revolutionary War. (John Kelly/The Washington Post)

He can’t consult photographs, of course. Paintings are useful, though only the wealthiest could afford to sit for a portrait. So Marko ferrets out information in other ways. “I’m like a terrier,” he says.

Marko scours 18th-century newspapers for stories that might include an admonition to be on the lookout for deserters from the American army or navy.

“It may say something like, ‘He went away wearing a blue coat with white lapels and a hat with silver edging,’” Marko says.

Newspaper ads can be useful, too. After Charles Lee, a general in the Continental Army, was captured and released by the British, he placed an ad describing his uniform. He wanted it back.

Marko looks at Colonial records to see how many yards of fabric were ordered, what colors, what sorts of hats and boots, how many plumes or bits of lace or piping.

Marko has written two books on Revolutionary War uniforms, illustrated with examples he has painstakingly assembled.

Soldiers then wore a rainbow of colors. And the hated British weren’t the only ones in red coats. Some American soldiers wore them, too. One Connecticut regiment had red coats with yellow accents. The 4th New York Regiment had white coats with red accents. The drummers for one New Hampshire regiment had green breeches and canary yellow coats.

If they got coats at all. Uniforms were hit and miss, and many soldiers suffered without boots or coats. With no standing army, the Americans sort of made it up as they went along. Nearly every unit was different. Marko has counted 66 styles of uniform between 1775 and 1783, just for Connecticut alone.

“That’s one state,” he says.

Many uniforms were modeled after European designs, especially if the commander came from there. Casimir Pulaski ordered fur trim for the uniforms worn by his men. It was what he was used to back home in Poland. And besides, how cool is a fur-trimmed uniform?

“These were literally amateur soldiers, but they tried to put on a military appearance,” Marko says.

Marko lives in the District with his wife, Nancy Aherne. I think he must have gotten the uniform bug as a boy. During the Depression, his mother ran a dress shop out of the family’s Chicago apartment. One of her clients was Elizabeth D. Brundage, wife of Olympic bigwig Avery Brundage. She gave young Marko a lavishly illustrated book about Napoleon. It was in French, but that didn’t matter.

“The pictures told me much more,” Marko says. It was a short leap from poring over color plates in a book to collecting tiny toy soldiers to wondering how the real soldiers were arrayed upon the battlefield.

Although Marko is interested in all Revolutionary War-era uniforms, he’s especially interested in men pictured as wearing a distinctive golden eagle medal. It’s the symbol of the Society of the Cincinnati and was designed by Pierre L’Enfant.

“Portraits with eagles have to be somebody,” he says. Through Marko’s work, the society has been able to identify specific early members.

If you like history, you should visit Anderson House. Built in 1905 by Larz and Isabel Anderson — he a diplomat, she an heiress — it’s a bit of Gilded Age splendor near Dupont Circle.

The hereditary-membership society has been trying to shed its image as a bastion of pedigreed blue bloods, with more public programs and museum exhibits. Visitors can see how the One Percent used to live and check out the current exhibit on the War of 1812.

And there’s that gem of a library, devoted to military history. If you go on a Thursday, you’ll probably see Marko.