Shakespeare invented swagger. No, really. He did. In his 1590 play A Midsummer's Night's Dream, Puck says "What hempen homespuns have we swaggering here?" This is probably taken from the Old Norse word sveggja ("to sway"), which is probably from the Proto-Germanic word swingan ("to swing"), which is probably from the Proto-Indo-European word sweng ("to turn"). Anyway, when Shakespeare used it, swagger meant "walking pompously". Pompous people often decorate themselves with, and use, ornaments, or something? So somehow the word developed into "material", though it also kind of meant "cool" in colloquial terms, as developed from "pompous". Acronyms for the word, such as stuff we all get and secretly we are gay are apocryphal, and by now alterations have appeared, like schwag and swagg. It's complicated. Swagger also still exists today.
Adam Aleksic, a rising sophomore studying linguistics and government at Harvard University, has been described as the internet's sixth most famous etymologist. He also has disturbing interests in politics, vexillology, geography, board games, conlanging, and law.