Yuzhno-Sakhalinsk began as a small Russian settlement called Vladimirovka, founded by convicts in 1882. The Treaty of Portsmouth in 1905, which brought an end to the Russo-Japanese War of 1904–1905, awarded the southern half of the Sakhalin Island to Japan. Vladimirovka was renamed Toyohara (meaning "bountiful plain"), and was the prefect capital of Japanese Karafuto Prefecture.