A country or area in which another country has power to affect developments although it has no formal authority.
Answer:
Following the Swedish defeat in the Finnish War of 1808–1809 and the signing of the Treaty of Fredrikshamn on 17 September 1809, the eastern half of Sweden, the area that then became Finland was incorporated into the Russian Empire as an autonomous grand duchy
Explanation:
The name of the device is the <span>Fessenden oscillator. It was made to allow submarines to communicate through Morse code. This way they could avoid communication being intercepted.</span>
