The first five disciples ( Pancha Vaggiya Bhikkhus ): Kondanna, Vappa, Bhaddiya, Mahanama, and Assaji.

The Sermon that Led to the First Arahants

The Buddha analyzes the human person through five components, proving that none of them can be considered a permanent "Self" or "Atman":

After hearing this discourse, all five monks attained full enlightenment (Arahantship) by liberating their minds from all taints through non-clinging.

Location: Isipatana Deer Park in Varanasi.