Who was the president in 1866?
This depends on the country. See related questions or re-ask your question specifying the country.
United States: Andrew Johnson.
Following Abraham Lincoln's assassination on April 15, 1865, Vice President Andrew Johnson (born December 29, 1808 in Raleigh, North Carolina; died July 31, 1875 in Elizabethton, Tennessee) became the seventeenth President of the United States, serving from 1865 April 15 to 1869 March 4.
Why did president Johnson veto the bill extending the freedmen's Bureau and the Civil Rights Act oh 1866?
Relating to revenue cutters and steamers, vetoed February 20, 1845. Veto Overridden. The Senate overrode the veto on March 3, 1845 by a vote of 41 yeas to 1 nay. The House overrode the veto on March 3, 1845 by a vote of 127 yeas to 30 nays. Source: http://wapedia.mobi/en/List_of_United_States_presidential_vetoes#John_Tyler The Civil Right's Act of 1866 was NOT the first. It was passed by Congress on April 9, 1866 over the veto of President Andrew…