They were not particularly integrated. Many of the territories became their own states like Ukraine, the Baltic states, etc. They were totally dependent on the Reich for financial and governmental support but they were independent states. Many of the newly created countries in the east almost immediately were at war with the Bolsheviks after obtaining independence, i.e. Ukraine and Poland. These states ONLY became independent in 1918 as a political move to appease Wilson's 14 Points. Poland is a special place because after conquering the territory in 1916, the Germans and Austrians agreed to split up Poland between themselves. They created administrative districts in the area. The Germans, in particular, were keen on incorporating the population into the Reich. As the army spearheaded into the area, they were improving the roads, the trains, healthcare (by that, I mean they sprayed chlorine (NOT GAS) to get rid of diseases and deloused them of lice. After the treaty, Ludendorff left 1 million troops to occupy the territories since they lacked a policing force. The Armistice signed in November 1918 required that the Reich to remove all of its troops from the newly acquired territories.