They were a faction of the Marxist Russian Social Democratic Labour Party founded by Vladimir Lenin and Alexander Bogdanov.
In 1912 they split from the RSDLP and formed their own party. Five years after they took power in Russia overthrowing the republican government created after the abdication of the Tsar a couple of months before. The Bolsheviks lead both the February and October Revolution and became the only ruling class in Soviet Russia and the Soviet Union.
The Bolshevik was a communist regime that was able to defeat the white armies, or the Melsheviks(?) (Sorry can't spell it), who only were able to fight together because they didn't want communism.
The white army was co.mprised of people who still wanted the noble family, those who wanted democracy, and people who just don't like communism, while the boshelviks were communists who wished to place the whole country under their ideology
The commander's name is Carleton. By that point, the british empire already started to made effort to abolish slavery before united states. So Carleton believed that returning the escaped slaves to Washington would be dishonorable.
Washington keep pushing him for several years for the return of the slaves until he eventually gave up and asked for compensation instead.