It's a bit more complicated. There were a handful of Americans executed for treason during the Revolution. And the first person executed by federal authority was a Mexican citizen, Hipolito Salazar, during the Mexican-American War. On Salazar, see: www.historynewsnetwork.org/article/trea...
The only capital sentence for treason carried out under United States law shows the way that racism is embedded in the idea of national belonging.
"The first person to be executed for treason in the US was not a spy or someone who sold secrets to a foreign government. It was not a Confederate general who took up arms against his government. It was an abolitionist named John Brown." from @nhannahjones.bsky.social www.nytimes.com/2026/02/13/m...