Learn Russian: Это был жестокий человек.

When introducing or identifying someone, Russian uses the fixed neuter pronoun это to mean 'this' or 'that'. If you used он, the sentence Он был жестокий человек would mean 'He was a cruel man' rather than 'That was a cruel man.'

Why is the verb был masculine if the sentence starts with the neuter word это?

In sentences that use это to introduce a noun, the past tense verb 'to be' agrees with the noun being introduced, not with это. Since человек is masculine, the verb must be the masculine был.

Why use человек instead of мужчина to translate 'man'?

While мужчина specifically means a male adult, человек means 'person' or 'human'. In Russian, when describing someone's fundamental character or personality traits, it is much more natural to use человек.

Does the ending of жестокий follow a specific spelling rule?