Holy Roman Empire electorate created by Albert the Bear in 1157; nucleus of Hohenzollern power and precursor to the Kingdom of Prussia.
Entered into a personal union with the Duchy of Prussia in 1618 as Brandenburg-Prussia when John Sigismund inherited Prussia; its distinct legal status within the Holy Roman Empire ended formally in 1806 when the Empire dissolved and all Brandenburg territories were subsumed into the Kingdom of Prussia.
The atlas holds 5 border frames for Margraviate of Brandenburg — the shape you scrub through changes in 1157 · 1240 · 1297 · 1356 · 1436.
Traces the Hohenzollern state from its Brandenburg origins; Harvard University Press; confirmed via Amazon, Goodreads, and Harvard UP page.