The history of Bratsk begins in **1631**, when a detachment of Cossacks led by the Yenisei Pentecostal **Maxim Perfilyev** founded a wooden fortification on the Angara River — the Bratsk Ostrog (fortress). Its main task was the collection of *yasak* (a tax in kind, mainly furs) from the local population and the further exploration of Siberian lands. The name "Bratsky" originated from the fact that the Cossacks called the indigenous people, the Buryats, "Bratsky people". The fortress was relocated several times and, from 1654, finally settled at the mouth of the Oka River, quickly becoming an important outpost for Russian explorers and a starting point for expeditions deep into Siberia and the Far East.
Initially, the Bratsk fortress served not only as a military and administrative centre but also as a place of exile — at various times, Archpriest Avvakum and the writer Alexander Radishchev served sentences here. A pivotal turn in the city's history occurred in the mid-20th century, when the decision was made in 1954 to build the **Bratsk Hydroelectric Power Plant (HPP)**, one of the largest hydroelectric stations in the world. The construction of the HPP became a major national priority project, attracting thousands of enthusiasts from all over the country. As a result of the creation of the Bratsk Reservoir, the historic village of Bratsk fell into the flood zone, and the modern city was officially formed on **December 12, 1955**, from several workers' settlements. Cheap electricity from the HPP facilitated powerful industrialisation: following the hydroelectric station, the Bratsk Aluminium Plant and a timber processing complex were built.
In the 17th–18th centuries, the economy of the Bratsk fortress was built on the fur trade and tax collection. The fortress was a typical example of Russian wooden defensive architecture, and one of its watchtowers has been preserved — it was transported in 1959 to the Kolomenskoye Museum-Reserve in Moscow. Later, with the loss of military significance, the fortress turned into a village whose inhabitants engaged in agriculture and cartage. Modern Bratsk, which grew in the taiga thanks to the labour of the HPP builders, inherited the pioneer spirit from its predecessors and is today one of the key industrial centres of Eastern Siberia.