Alexander Slidell Mackenzie (1803–1848), born Alexander Slidell, was a U.S. naval officer most famous for his 1842 decision to execute three suspected mutineers aboard a ship under his command, the USS Somers. Mackenzie was also an accomplished man of letters, producing several volumes of travel writing and biographies of early important U.S. naval figures, some of whom he knew personally. Mackenzie was the brother of U.S.