One example worth looking into might be the Eastern Roman Empire’s Varangian Guard[1]. This elite force was primarily composed of Germanic mercenaries who didn

One example worth looking into might be the Eastern Roman Empire’s Varangian Guard[1]. This elite force was primarily composed of Germanic mercenaries who didn’t care much for politics - in a foreign land far away from their own - as long as they got paid and could retire wealthy back home. Conversely, the Western Roman Empire’s Praetorian Guard was composed of elite Roman soldiers, who had far more skin in the game of imperial politics, and occasionally offed an emperor they didn’t like. So the condensed answer from this historical example might be: pay disinterested professionals handsomely, but maybe don’t expect for them to stick around forever. Not sure how well this advice works in the digital age though. YMMV. [1] https://en.m.wikipedia.org/wiki/Varangian_Guard https://en.m.wikipedia.org/wiki/Varangian_Guard