Equilibrium was established by Plutarch in The Parallel Lives (2d cent. a.d.). His method was comparative, e.g., Theseus is matched with Romulus; Demosthenes with Cicero. In his conclusions, he evaluates the connection between the moral standards and worldly achievements of each. St. Augustine turned the same critical judgment on himself in his Confessions (4th cent.), comparing his character and conduct before and after his conversion to Christianity.

During the Middle Ages credibility continued to be sacrificed to credulity. In the hagiographies, or lives of the saints, human flaws and actual events were bypassed in favor of saintly traits and miracles. Yet the few secular biographies produced in that era, Einhard's Life of Charlemagne (9th cent.), Eadmer's Life of St. Anselm (12th cent.), Jean de Joinville's Memoirs of St. Louis IX (13th cent.), and Jean Froissart's Chroniques (15th cent.), redeem the genre with their lively depiction of personalities and events.

With the Renaissance came rekindled interest in worldly power and self-assertion. Benvenuto Cellini's Autobiography (16th cent.), recounting his escapades and artistic achievements, is a monument to the ego. Saint-Simon's Memoirs (late 17th cent.) describe Louis XIV and his court at Versailles and record the effect of the monarch's absolute power on the daily lives of others. In England, Samuel Pepys's Diary, John Evelyn's Diary, Izaak Walton's Lives and John Aubrey's Lives of Eminent Men (all mid-17th cent.) introduced informality and intimacy to their treatments. Each wrote about contemporaries who were their friends or acquaintances.

By the 18th cent. literary biography (works about poets and men of letters) had become an important extension of the genre. Dr. Johnson's Lives of the Poets (1779-81) set the example for James Boswell's Life of Samuel Johnson (1791), the first definitive biography. This monumental work was drawn not only from Boswell's exact recollections of conversations with Johnson, but from letters, memoirs, and interviews with others in Johnson's circle as well. Two equally celebrated autobiographies, Benjamin Franklin's, noted for its practicality, and Jean Jacques Rousseau's, noted for its candor, also mark this age.

Among the avalanche of biographies and autobiographies published in the 19th cent. Goethe's Dichtung und Wahrheit (1808-31), Thomas Carlyle's Sartor Resartus (1833-34) and Frederick the Great (1858-65), and Ernest Renan's Life of Jesus (1863) are important. Also noteworthy was the publication of the Dictionary of National Biography (1882), edited by Leslie Stephen.

As a result of Freud's defining of the unconscious, the 20th cent. produced a new sort of biography—one that used the technique of psychoanalysis on the subject. Examples of such works are Freud's own Leonardo Da Vinci (1910) and Anaïs Nin's Diaries (1931-44). As antidotes to the tradition of the official biography Lytton Strachey wrote Eminent Victorians (1918) and Queen Victoria (1921), works that deflate and debunk.

Twentieth-century biographers often sought to make structure a reflection of theme. Henry Adams's Education of Henry Adams (1918) explores the metaphor of the title; Thomas Merton's Seven Story Mountain (1948) follows the analogue of Dante's Inferno; and Lillian Hellman's Pentimento (1973) presents portrait sketches of the people in her life as seen from the vantage point of her maturity. Notable literary and scholarly biographers of the 20th cent. include Harold Nicolson, Allan Nevins, D. S. Freeman, André Maurois, J. H. Plumb, Carl Sandburg, Dumas Malone, Elizabeth Longford, and Leon Edel.

Motion pictures and television have adapted the form of biography to their own needs. With Paul Muni as Louis Pasteur, Charles Laughton as Rembrandt, or Spencer Tracy as Thomas Edison, films retraced for new audiences, although often in a romanticized fashion, the paths to success taken by men of intelligence and character: the old Plutarchian formula. Documentary biographies, composed of newsreel clips and photographs, have been made about public figures such as Eleanor Roosevelt, the Duke of Windsor, and Martin Luther King, Jr.

Two innovations of television are the dramatic documentary ("docudrama") and the interview. Ken Russell's film essays, commissioned by the British Broadcasting Company (1965-70), on Elgar, Rossetti, Delius, Richard Strauss, and Isadora Duncan attempted to convey the essence of a person's character and work rather than just the facts of his life. Homage to Plutarch was evident again in the format of Edward R. Murrow's interview program, Person to Person (1953-59), where guests like Marilyn Monroe and Sir Thomas Beecham were deliberately paired.

The television interview was expanded by such talk show hosts as Dick Cavett, David Frost, and Charlie Rose, who have led their usually well-known guests to talk about their lives for an hour or longer. The expansion of oral history programs, in which prominent figures record their reminiscences, are also providing a body of primary biographical source material. With the advent of cable television, biography became a daily staple of various channels and biographies were offered as part of the programming on channels devoted to a number of special subjects, e.g., history and education.