Karl Barth Watch ID Mystery

Hello old watch nerds comrades,

I have a bit of a different request for you today. Instead of having a watch in front of me that I need help identifying, I'm hoping someone can help me identify the wristwatch of a famous* theologian: Karl Barth.

*Insofar as theologians can still be "famous"...

Barth was a Swiss Protestant theologian (1886-1968) known for, among other things:

• Socialist organizing in the 1910s, known as the "Red Pastor" of Safenwil
• Authoring the Barmen Declaration of religious resistance to the ****s, and subsequently being expelled from Germany
• Almost (not really) finishing the most massive systematic theology, his Kirchliche Dogmatik (Church Dogmatics), which nevertheless runs over 9m pages in 13 published volumes.

However, what's really important here is that I can't figure out what sort of wristwatch he wore. In photos, it's clear he still regularly used a pocket watch when he was out and about (such a child of the (18)'90s). But he also clearly wears a wristwatch at times as well, and I want to know what it was (or as close as possible).

I'll attach what photos I've found, though some of them are pretty useless. I'll also give you my initial theories:

• In one of the photos (the Getty, I think), it looks like the watch has a “small seconds” circle at the bottom, with maybe Arabic indices and cathedral hands?
• Most of that (except the cathedral hands) would be very similar to the military watches Switzerland produced for the Allies in the early 1940s.
• Since Barth joined the Swiss militia in the early '40s and not the regular military, I would anticipate it being similar in style to those watches, but a bit more “civilian” and perhaps made earlier (1930s?).
• I think 1930s was sort of the beginning of the “Calatrava” style, which seems like this watch might fit in that category.
• However, since the best pictures are from the late 1950s, I really can’t eliminate anything between 1930 and 1960.

Any and all help appreciated. Get on it, gumshoes!