Northwestern Russia is a federal district of Russia.
Russian is the native language of the majoraty of Northwestern Russia inhabitants. Important minoraty languages are: Finnish, Karelian and Veps languages in Karelia republic and Komi laguage in Komi republic. Almost all Finnish, Karelain, Komi and Veps speakers are bilingual and are fluent in Russian, aside from their native languages.
Basic English is widely understood in big cities, while in smaller cities and the countryside it can be very difficult to find an English speaker. German can also be useful. Older generations (over 30 years old) are less familiar with foreign languages than younger people.