Śvetāmbara and Digambara are both very old Jain traditions, but the formal division is generally understood to have developed later, not fully from the very beginning.

In short:

• Digambara tradition preserves the ideal of complete nudity for monks.
• Śvetāmbara tradition allows white clothes for monks.

How the division happened

According to the traditional Jain account, the split is linked to a great famine in Magadha, after which:

• Bhadrabahu and his followers moved south.
• The monks who stayed in the north later came to use white cloth, and this line became associated with the Śvetāmbara tradition.
• The southern line preserved the practice of nudity, becoming Digambara.

When did it divide?

Historically, scholars generally place the clear sectarian separation around the early centuries BCE to early centuries CE, and it became more firmly established by about the 4th–5th century CE.

Important point

It is best to say:

• They are both ancient
• But their split was gradual
• Not necessarily a single sudden event

So, Digambara is usually considered the older monastic form, while Śvetāmbara emerged later as a distinct organized tradition through historical development.

If you want, I can also explain the main doctrinal differences between Śvetāmbara and Digambara in simple language.