 When the Brandenburg elector Frederick II Irontooth chose Berlin-Cölln as his residence, he had the City Palace erected on the island from 1443 onwards, suspiciously eyed by the citizens.When a new bridge was erected from 1661, the Hohenzollern electors funded part of the costs.Under the rule of Elector Frederick III, in 1691, plans for a new construction were designed by Johann Arnold Nering in a Baroque style, consistent with the adjacent Palace.