Reuss Older Line Timeline
here is a link to the historical timeline of Thuringia
and here is a link providing historical developments of Germany at any given time period.
A good source for local history timelines can be found in village chronicles. These are taking historical developments of specific areas into account, and let the researcher have a glimpse of ancestors' lives from various points of view. Ortschroniken can usually be retrieved through a mayor's office or historical societies. A Google search may assist with availability.