He remains the only U.S. president who could converse in Russian.[231]

Legacy
Historical reputation
Official portrait of Adams by George Peter Alexander Healy, c. 1858
Adams is widely regarded as one of the most effective diplomats and secretaries of state in American history,[232][233] but scholars generally rank him as an average president.[234][235] Adams is remembered as a man eminently qualified for the presidency, yet hopelessly weakened in his presidential leadership potential because of the 1824 election. Most importantly, Adams is remembered as a poor politician in an era when politics had begun to matter more. He spoke of trying to serve as a man above the "baneful weed of party strife" at the precise moment in history when the Second Party System was emerging with nearly revolutionary force.[170] Biographer and historian William J. Cooper Jr. comments that Adams "does not loom large in the American imagination", but that he has received more public attention since the late 20th century due to his anti-slavery stances. Cooper writes that Adams was the first "major public figure" to publicly question whether the United States could remain united so long as the institution of slavery persisted.