Orthodox Church formed a significant part of Kiev's infrastructure and business activity. In the late 1840s, the historian, Mykola Kostomarov (Russian: Nikolay Kostomarov), founded a secret political society, the Brotherhood of Saint Cyril and Methodius, whose members put forward the idea of a federation of free Slavic people with Ukrainians as a distinct and separate group rather than a subordinate part of the Russian nation; the society was quickly suppressed by the authorities.
Following the gradual loss of Ukraine's autonomy, Kiev experienced growing Russification in the 19th century by means of Russian migration, administrative actions and social modernization. At the beginning of the 20th century, the city centre was dominated by the Russian-speaking part of the population, while the lower classes living on the outskirts retained Ukrainian folk culture to a significant extent. However, enthusiasts among ethnic Ukrainian nobles, military and merchants made recurrent attempts to preserve native culture in Kiev (by clandestine book-printing, amateur theatre, folk studies etc.)
During the Russian industrial revolution in the late 19th century, Kiev became an important trade and transportation centre of the Russian Empire, specialising in sugar and grain export by railway and on the Dnieper river. As of 1900, the city had also become a significant industrial centre, having a population of 250,000. Landmarks of that period include the railway infrastructure, the foundation of numerous educational and cultural facilities as well as notable architectural monuments (mostly merchant-oriented). The first electric tram line of the Russian Empire was established in Kiev (arguably, the first in the world).
Kiev prospered during the late 19th century industrial revolution in the Russian Empire, when it became the third most important city of the Empire and the major centre of commerce of its southwest. In the turbulent period following the 1917 Russian
