==dates== 
 Since Foner's highly influential book appeared in 1988, historians have used 1863 as the start of Reconstruction. It began in each state as soon as federal troops were in control, and Lincoln was very active in the Reconstruction of Louisiana, Arkansas, Tennessee, etc.  "Reconstruction" also means the postwar era for the entire US, 1865-1877 (not merely the South), so I rephrased the lede to reflect that dominant interpretation.