Abraham Lincoln was the 16th United States president. He was born on February 12, 1809 in Hardin Country, Kentucky. He served the Unites States from March 4, 1861 until his assassination in April 14, 1865. He was assassinated by John Wilkes Booth at Ford's Theatre in Washington. 

 Before he reigned the United States, he was a lawyer, an Illinois legislative member and a member of the House of Representatives of America. Lincoln won the election of the United States president from the Republican Party in 1860. Since he against the slavery in his country, he made a decree in order to abolish the slavery. This happened through the Proclamation of Emancipation in 1863. 

 On January 1st, 1863, Lincoln released a Proclamation of Emancipation which frees up the slavery in several states. After the war, the government started to reconsrtuct the United States. This reconstruction was planned for the political field dealing with the states merger.  The horrible slavery system that tortured the black people's life in America can be erased due to the reconstruction period. Since this passion in reconstructing the United States in terms of its politic, economy and social of Abraham Lincoln was stopped due to his assasisination. Therefore his vice , Andrew Johnson continued this noble purpose. 
References:

 https://www.academia.edu/19810281/Abraham_Lincoln_Pemimpin_Demokrasi
https://id.wikipedia.org/wiki/Abraham_Lincoln
https://www.whitehouse.gov/about-the-white-house/presidents/abraham-lincoln/