Jainism is regarded in tradition as an eternal Dharma (nitya-dharma), not started by a single founder. It is believed to have existed long before recorded history, taught by a line of Tirthankaras in successive cosmic eras.

Key points:

• The Jain tradition lists 24 Tirthankaras. The first Tirthankar in this cycle is Rishabhanatha (also called Adinath).
• The 24th Tirthankara was Mahavira (Vardhamana), who is the most recent great teacher whose life is dated to around 599–527 BCE. He is traditionally considered the one who organized and consolidated Jain sangha (monastic communities) in the northern Indian region of Vajji (Vaishali) and nearby areas.
• Both Digambara and Śvetāmbara traditions agree that Mahavira was the last Tirthankar of this cycle, but they differ on some details of the earlier Tirthankaras and on the exact sequence of events.

If you’d like, I can provide the core Jain scriptures’ phrasing (with meanings) related to the Tirthankaras or point you to a Jain Knowledge page for deeper study.