What grammatical error exists in 'Magna pars nostrī hūc vēnērunt cōnficiendae pācis grātiā.'?

The phrase 'Magna pars nostrī hūc vēnērunt cōnficiendae pācis grātiā' contains a grammatical error related to the form of the pronoun used. In this context, 'nostrī' is in the genitive case and means "of us," which does not agree with the construction of the sentence that requires the pronoun to be in the nominative case, as it functions as the subject of the phrase. The correct form should be 'nostrum,' which is the nominative plural, agreeing with 'pars,' which is a feminine noun in the nominative singular. Thus, 'magna pars nostrum' properly translates to "a great part of us" instead of implying a possessive relationship that 'nostrī' suggests.

By substituting 'nostrī' with 'nostrum,' the sentence aligns correctly with the grammatical rules regarding the agreement of nouns and their governing pronouns in Latin.