In Jain Dharma, Rushabhdev (Rishabhadeva / Ādināth) is the first Tirthankar, not a Hindu god.

So, from the Jain viewpoint:

• He is not compared as an equivalent to any Hindu deity.
• He belongs to the lineage of 24 Tirthankars.
• He is revered as a spiritual teacher and ford-maker who showed the path of dharma, renunciation, and liberation.

If you mean which Hindu deities are described as ancient or early in timeline, Jain tradition does not place Rushabhdev in the same category as a god within Hindu theology. In Jain understanding, he stands as a Tirthankar of the present time-cycle.

If you want, I can also explain Rushabhdev in Jain scriptures and his place in history.