The word 'them' has a direct lineage from Old English, evolving from the dative plural form 'þēom' of the pronoun 'hīe'. It is part of the core set of English personal pronouns inherited from Proto-Germanic, ultimately tracing back to Proto-Indo-European demonstrative roots. Over time, 'þēom' lost its strictly dative case function and became the general object form for the plural third person, supplanting the old accusative form. Its modern spelling and pronunciation stabilized in Middle English, solidifying its role as the essential objective counterpart to the subjective pronoun 'they'.

The word is a simplex pronoun. It originates from Old English 'þēom', the dative plural form of the third-person plural pronoun 'hīe' (they). Its functional role is as an object pronoun.