reconstruction
/ˌriːkənˈstrʌkʃən/
noun
plural -tions
[noncount] :the act or process of building something that was damaged or destroyed again
[noncount] :the process of putting something (such as a country) back into a good condition
a process in which an event or series of events is carefully examined in order to find out or show exactly what happened [noncount]
or Reconstruction [noncount] US :the period from 1867 to 1877 when the southern states joined the northern states again after the American Civil War