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The House of Representatives impeached President Andrew Johnson in February 1868; he was acquitted at his Senate trial in May 1868.
Hannibal Hamlin was Lincoln's running mate in the 1860 election and was Vice President during most of Lincoln's presidency. Andrew Johnson was Lincoln's running mate in 1864. He took office as Vice President the month before Lincoln was killed.
Andrew Johnson took the Oath of Office on April 15, 1865, the day Abraham Lincoln died. He didn't have a big inaugural ball, parade, etc. that elected presidents get.
January
Andrew Jackson died on June 8, 1845. Andrew Johnson died on July 31, 1875. (Although you put your question in the Andrew Jackson category, your misspelling looks a lot more like Johnson.)
Only Lincoln - inaugurated a month before the war started, and re-inaugurated a month before it (effectively) ended. If you include the small actions in North Carolina, then you have to count Andrew Johnson as a wartime president.
Probably Andrew Johnson. The House was pretty much against him from the start and impeached him. Of course, Wm Henry Harrison had only one month and he was sick in bed most of that time, so he may have had less influence than Johnson.
His father rescued a man from drowning in icy waters and suffered severe exposure and exhaustion and died a month later at age 36. His mother remarried and lived to be 73 and dies of natural causes.
march
Nine. Five of them were not elected to a term in their own right - Tyler, Fillmore, Andrew Johnson, and Ford. the other four were elected to their own term after finishing the term of their deceased predecessors - Theodore Roosevelt, Coolidge, Truman, and Lyndon Johnson.
Jacob Johnson (1778-1812) died of an apparent heart attack at age 33 in January 1812, which may have resulted from exertion he suffered when he rescued two men from drowning a month earlier. His son, future US president Andrew Johnson, had just turned 3 years of age (born December 29, 1808).