Few people today remember the important contribution that the Protestant Reformation made to the clothing industry. In the early days of John Calvin's ministry, he realised that allowing freedom under the cassock, so to speak, had contributed to the sexual excesses that had marked some aspects of pre-Reformation Catholicism. And so he invented underpants, as a way of keeping his clergy under control. They also helped in draughty churches in alpine winters.
Of course, the French-born theologian couldn't market in his own country, which was still strongly Catholic, and toying with the idea of having its own Pope. So instead, he had to launch in the more Protestant countries, and in a small way.
So to start with, he opened outlets in the German-speaking cantons of Switzerland, and parts of Prussia, Bavaria and Saxony. And, due to endemic malnutrition in the Europe of the time, he only manufactured the clothing in "small". And so a brand was born. "Calvin - Klein".
Inspired by @theAlethiophile. Though I'm sure it's been done before.