Blackshirts were the fascist military wing under the leadership of , while the Bolsheviks were a communist group led by .

The correct answers are:

- Benito Mussolini;

The so called Blackshirts were originally a paramilitary wing of the Nationalist Fascist Party in Italy, and they were serving Benito Mussolini. After the year of 1923, they became an all-volunteer militia in the Kingdom of Italy.

- Vladimir Lenin;

The Bolsheviks were a wing of the Russian Social-Democratic Worker's Party, and they were led by Vladimir Lenin in an attempt to gain control over the country, and indeed they succeeded in their goal.

Explanation:

- Benito Mussolini ;and - Vladimir Lenin;

a drastic rise in oil prices ended decades of postwar.