Helsinki Cathedral is the Finnish Evangelical Lutheran cathedral of the Diocese of Helsinki, located in the neighborhood of Kruununhaka in the center of Helsinki at the Senate Square. The church was originally built from 1830 to 1852 as a tribute to the Grand Duke of Finland, Tsar Nicholas I of Russia. Alexander II (April 29, 1818 – March 13, 1881) was Emperor of Russia, King of Poland and Grand Duke of Finland from March 2, 1855 until his assassination in 1881.