President Andrew Johnson also served as a Senator from Tennessee in 1875, 7 years after the Senate acquitted him of impeachment charges.

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In 1992 he published Grand Inquests, a 278-page history of the 19th century impeachment trials of Justice Samuel Chase and President Andrew Johnson.

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Andrew Johnson, our first impeached President, was said to have waved around his pocket constitution so often that he resembled a newsboy hawking the daily paper.

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As Nixon resigned when the process was just beginning, the only president to have been through the whole process was Andrew Johnson, impeached by the House in 1868 on 11 counts, strongly political in flavour.

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In 1808, Andrew Johnson, the 17th U.S. president, was born.

CNN: Monday,