Rhetoric was likely originally crafted as a means of conveying a speaker's thoughts and ideas in a manner that was both effective and aesthetically pleasing. The earliest evidence of organised rhetorical thinking and techniques comes from ancient Greece, around the beginning of the fifth century, BC, where orators like Corax and Tisias advocated developing persuasive techniques for use in legal contexts. Other contributors during these early stages would eventually help form and systemise the core teachings as well as develop a body of literature on topics of oratory and delivery - figures included Gorgias, Protagoras, and Antiphon. However, it wouldn't be until Aristotle published *Rhetoric* sometime between 335 and 322 BC that more concrete guidance was laid out. Even when rhetoric had spread more extensively, Aristotle work would form the basis of much rhetorical training even centuries afterwards.
Since those earliest roots of rhetoric's origins, we now see it in an expansive variety of situations for various purposes ranging from politics to teaching.