An oratorio is a large musical composition including an orchestra, a choir, and soloists. Like an opera, an oratorio includes the use of a choir, soloists, an ensemble, various distinguishable characters, and arias. However, opera is musical theatre, while oratorio is strictly a concert piece—though oratorios are sometimes staged as operas, and operas are sometimes presented in concert form. In an oratorio there is generally little or no interaction between the characters, and no props or elaborate costumes. A particularly important difference is in the typical subject matter of the text. Opera tends to deal with history and mythology, including age-old devices of romance, deception, and murder, whereas the plot of an oratorio often deals with sacred topics, making it appropriate for performance in the church. Protestant composers took their stories from the Bible, while Catholic composers looked to the lives of saints. Oratorios became extremely popular in early 17th century Italy partly because of the success of the opera and the Church's prohibition of spectacles during Lent. Oratorios became the main choice of music during that period for opera audiences.

Jean-François Le Sueur (or Lesueur; pronounced [ʒɑ̃ fʁɑ̃swa lə sɥœʁ]) (15 February 1760 – 6 October 1837) was a French composer, best known for his oratorios and operas.

He was born at Plessiel, a hamlet of Drucat near Abbeville, to a long-established family of Picardy, the great-nephew of the painter Eustache Le Sueur. Beginning as a chorister at the collegial church of Abbeville, then at the cathedral of Amiens, where he pursued his music studies, Le Sueur was named chorus master at the cathedral of Sées. He went to Paris to study harmony with the Abbé Nicolas Roze, chorus master at the Saints-Innocents. Le Sueur was named to positions at Dijon (1779), Le Mans (1782), then at Tours (1783) before he succeeded Roze at the Saints-Innocents at Paris. Finally in 1786, after a competition, he was made music director at Notre-Dame de Paris.

For the Feast of the Assumption, he innovated by introducing an orchestra, with great success, and his sacred concerts at the main feasts of the Church filled the cathedral to overflowing but incurred resistance in ecclesiastical circles. He replied by publishing a pamphlet Exposé d'une musique imitative et particulière à chaque solennité (1787). The cathedral chapter decided to reduce its musical budget in a time of financial crisis for France, which constrained Le Sueur to give up the important musical Masses that he specialised in, and to give up his position.

John Adams (October 30, 1735 (O.S. October 19, 1735)  – July 4, 1826) was an American Founding Father, and the second President of the United States (1797–1801). He was also a lawyer, statesman, diplomat, political theorist, and a leading champion of independence in 1776. Hailing from New England, Adams, a prominent lawyer and public figure in Boston, was highly educated and represented Enlightenment values promoting republicanism. A Federalist, he was highly influential and one of the key Founding Fathers of the United States.

Adams came to prominence in the early stages of the American Revolution. As a delegate from Massachusetts to the Continental Congress, he played a leading role in persuading Congress to declare independence and assisted Thomas Jefferson in drafting the Declaration of Independence. As a diplomat in Europe, he was a major negotiator of the eventual peace treaty with Great Britain, and chiefly responsible for obtaining important loans from Amsterdam bankers. A political theorist and historian, Adams largely wrote the Massachusetts Constitution in 1780 which soon after ended slavery in Massachusetts, but was in Europe when the federal Constitution was drafted on similar principles later in the decade. One of his greatest roles was as a judge of character: in 1775, he nominated George Washington to be commander-in-chief, and 25 years later nominated John Marshall to be Chief Justice of the United States.

Karina Gauvin is a Canadian soprano who has made several recordings and is especially recognised for her interpretation of Baroque music.Opera News stated that, "Gauvin knows how to rivet an audience in opera and concert. She has been a queen of Baroque opera for years. Her personality is big enough to dominate her elaborate wigs and costumes, and her soprano voice is like a clear, refreshing and inexhaustible spring that darts and sparkles around any ornamental obstacle in its way."

Born c. 1966 in Repentigny, Quebec Gauvin was the youngest of three children born to two both professionally trained opera singers who were never able to establish successful performance careers. With the encouragement of her mother, Lucie Gaudreau, she became a member of the Canadian Children's Opera Chorus at the age of 8. She sang in numerous concerts and operas with the chorus over the next eight years, including productions of Tosca and Wozzeck. As a teenager she began to study singing seriously with mezzo-soprano Catherine Robbin in Toronto. She moved with her family back to Montreal and shortly thereafter enrolled at McGill University where she majored in Art History. While there she sang in the university's chorus under conductor Nicole Paiement. Paiement convinced Gauvin to pursue a career as a singer, and she subsequently left McGill for the Conservatoire de musique du Québec à Montréal where she became a pupil of Marie Daveluy. She later studied in Glasgow with contralto Pamela Bowden at the Royal Scottish Academy of Music and Drama.

Sébastien de Brossard (12 September 1655 – 10 August 1730) was a French music theorist.

Brossard was born in Dompierre, Orne. After studying philosophy and theology at Caen, he studied music and established himself in Paris in 1678 and remained there until 1687. He briefly was the private tutor of the young son of Nicolas-Joseph Foucault, a collector and bibliophile. He became a very close friend to Étienne Loulié, one of the musicians who performed the Italianate works that Marc-Antoine Charpentier was composing for Marie de Lorraine, Duchess of Guise, better known as "Mademoiselle de Guise." While in Paris, he also became close to Samuel Morland, an English inventor and polymath who was working with Joseph Sauveur, a mathematician, on the Machine de Marly. It was during talks about music with Morland that Brossard deduced the role that a major third versus a minor third play in differentiating a major scale from a minor scale.

These contacts shaped Brossard's future preoccupations. He enthusiastically embraced Italian music; he became a collector of musical manuscripts and music treatises; he perfected his knowledge of musical theory; and autodidact though he was, he honed his compositional skills.