I think what most people have heard of is the Sacred Band of Thebes. https://en.wikipedia.org/wiki/Sacred_Band_of_Thebes https://en.wikipedia.org/wiki/Sacred_Ba

I think what most people have heard of is the Sacred Band of Thebes. https://en.wikipedia.org/wiki/Sacred_Band_of_Thebes https://en.wikipedia.org/wiki/Sacred_Band_of_Thebes However, I recall that there are several ancient Greek texts that reveal that "regimental love" was a known phenomenon throughout Greece.