In Western classical rhetoric, elocution was one of the five core disciplines of pronunciation, which was the art of delivering speeches. Orators were trained not only on proper diction, but on the proper use of gestures, stance, and dress. (Another area of rhetoric, elocutio, was unrelated to elocution and, instead, concerned the style of writing proper to discourse.)
Elocution emerged as a formal discipline during the eighteenth century. One of its important figures was Thomas Sheridan, actor and father of Richard Brinsley Sheridan. Thomas Sheridan's lectures on elocution, collected in Lectures on Elocution (1762) and his Lectures on Reading (1775), provided directions for marking and reading aloud passages from literature. Another actor, John Walker, published his two-volume Elements of Elocution in 1781, which provided detailed instruction on voice control, gestures, pronunciation, and emphasis.
With the publication of these works and similar ones, elocution gained wider public interest. While training on proper speaking had been an important part of private education for many centuries, the rise in the nineteenth century of a middle class in Western countries (and the corresponding rise of public education) led to great interest in the teaching of elocution, and it became a staple of the school curriculum. American students of elocution drew selections from what were popularly deemed "Speakers." By the end of the century, several Speaker texts circulated throughout the United States, including McGuffey's New Juvenile Speaker, the Manual of Elocution and Reading, the Star Speaker, and the popular Delsarte Speaker. Some of these texts even included pictorial depictions of body movements and gestures to augment written descriptions.
The era of the elocution movement, defined by the likes of Sheridan and Walker, evolved in the early and mid-1800's into what is called the scientific movement of elocution, defined in the early period by James Rush's The Philosophy of the Human Voice (1827) and Richard Whately's Elements of Rhetoric (1828), and in the later period by Alexander Melville Bell's A New Elucidation of Principles of Elocution (1849) and Visible Speech (1867).
In her recent book The Elocutionists: Women, Music, and the Spoken Word (University of Illinois Press, 2017), Marian Wilson Kimber addresses the oft-forgotten, female-dominated genre of elocution set to musical accompaniment in the United States.
An example of this can be seen in the Table of Contents of McGuffey's New Sixth Eclectic Reader of 1857: