How did impromptu bands of sailors in blackface become a significant channel of 19th century cultural diplomacy?  Go, read:

Brian Rouleau: “In the Wake of Jim Crow: Maritime Minstrelsy Along the Transoceanic Frontier”

And why not, indeed?  First, a growing network of 19th century canals brings together free and slave laborers from diverse transatlantic backgrounds and delivers their resulting mudsill melodies to cosmopolitan stages across the Northeast (see Lhamon’s Raising Cain ).  Then, in theatre districts at port towns like New York, Philadelphia, Baltimore, and Boston, countless mariners drink in the banjo-driven bones-laced pop music of the new blackface minstrel bands.  These same mariners subsequently find themselves on voyages to all points of the globe, surrounded by curious natives, called upon to represent U.S. culture (or even, in many cases, Western Civilization) to all manner of audiences.  So, what type of “culture” did these sailors share with their heathen hosts?

We have a minstrel band of 9 performers, that do beat Christy’s all hollow. One of them does up Lucy Long tip top, and they are always well received. Every Monday we have a performance—alternatively the theatre and “nigger band”—on these occasions the ship assumes a gala appearance and great things are done. … The Susquehannah has a theatre every Wednesday, the Winchester on each Fridays and the Mississippi on Tuesdays, so you see we do not lack for that kind of amusement. Society in China there is not and so we are obliged to turn our ships into playhouses, to interest the men, and amuse ourselves.

— Thomas Dudley, writing from the USS Powhatan at Hong Kong, 20 December 1853

But it wasn’t all in the name of fun and laffs:

For the seamen who blacked up, “demonstrating America” was not reduced to displaying feats of engineering. Rather, exposing the Japanese to American civilization meant educating them in the proper racial order. If the “Land of the Rising Sun” was to become civilized, its inhabitants would require instruction in the sort of prejudice befitting civilized peoples… — Rouleau

Rouleau’s essay catalogs unlikely maritime minstrel shows off the coasts of China, Japan, Liberia, and contextualizes some of the striking images found in MIT’s “Visualizing Cultures” collection.