After the Qajars lost a series of wars to Russia (Russo-Persian Wars 1804–1813 and 1826–28), it resulted in an enormous gain of influence by the Russian Empire in the Caspian region, which would last all the way up to 1946. All of Gilan was occupied and settled by Russians and Russian forces. Most major cities in the region had Russian schools and significant traces of Russian culture can still be found. This significant increase of Russian influence in the region would last all the way up to the 1946 and had a major impact on Iranian history, as it directly led to the Persian Constitutional Revolution.