That's where they got it from! Though indirectly.
The ratchet first appears in Spanish navajas, before 1800. It became prominent in the 19th century, sometimes combined with a pull-ring, though most of the time you pulled the locking tab with your fingers to unlock it and close it. To open it, you could throw the knife open, since it doesn't lock in the closed position. And the carraca (the ratchet) would make a cra-cra-cra sound. Not a stealth weapon!
19th century Spanish navajas, with and without a pull-ring
Later, in the 20th century, they'd introduce a more convenient lever instead of a pull-ring.
Spanish navajas with a lever, early 20th, mid-20th, and 21st century
In the late 19th century, the French industry started furiously copying Spanish designs and selling them back to Spain, adapting them, and keeping some design elements for knives made for local markets.
French navaja for the Spanish market
Around 1900, the French cra-cra (it's got many other names), clearly inspired by the navaja, was widely popular in France. It saw a lot of use, from gangsters to farmers and later to soldiers in the First World War. Note that in most of these the ratchet had only 2 pins (locks in the open position, and in the half-open position). So it made a cra-cra noise when you opened it. It had a pull-ring, and the handle material was wood or horn.
French cra-cra knives, from early to modern
In 1902, the German company Okapi gets founded, and mass-produces various knife models for export to German colonies. The knife that became so well-known that by now most people define it as "an Okapi" looks exactly like the French cra-cra, but with a characteristic "moon and stars" decoration on the handle, and with a ratchet like in Spanish navajas: many pins, 5 or 7 I think, locks in many positions, and makes a real racket when you open it. Cra-cra-cra-cra-cra. The handle material was bakelite or wood.
In 1988, the Okapi production (tools and trademark) moved to South Africa, where it's still mass-produced and widely popular. It's the same knife, except the handle material is resin-impregnated wood.
And later, the American company (with production in China) Cold Steel copied the whole thing yet again, and made the Kudu. I'm not sure about its locking mechanism, is it an actual ratchet or does it just lock in the open position? [EDIT: @balaclava-trismegistus informs us it's indeed a ratchet, thanks!] The handle material is "glass-reinforced Zy-Ex" (don't ask me. it's synthetic, that's all I know.)
I've also seen a modern German copy of the copy of the copy, fancy and expensive (whereas Okapis and Kudus are cheap), named after another African animal. But I didn't bookmark it, and I forgot what it's called, and now I can't find it.
Finally, there are some really bad Okapi knock-offs out there: the blade's bevel is very different (one of the great things about Okapis is that they're very easy to sharpen; this is the opposite), the handle's shape is less round, and it's just a bad construction. Avoid!
[For the cultural history of the Okapi as a knife of ill-repute, see here.]
