Between 1620 and 1622 Calderón won several poetry contests in honor of St Isidore at Madrid. Calderón's debut as a playwright was Amor, honor y poder, performed on June 29, 1623. This was followed by two other plays that same year: La selva confusa and Los Macabeos. Over the next two decades, Calderón wrote more than 70 plays, the majority of which were secular dramas written for the commercial theatres.
According to one of his biographers, Vera Tassis, Calderón served with the Spanish army in Italy and Flanders between 1625 and 1635; but this statement is contradicted by numerous legal documents indicating that Calderón resided at Madrid during these years. Early in 1629 one of his brothers was stabbed by an actor who took sanctuary in a convent; Calderón, accompanied by another brother and some constables, broke into the cloister and attempted to seize the criminal. (One of the nuns happened to be the daughter of fellow dramatist Lope de Vega.) The fashionable preacher, Hortensio Félix Paravicino, denounced Calderón's actions in a sermon preached before King Philip IV; Calderón retorted by introducing into El príncipe constante, a mocking reference to Paravicino's florid oratory. Calderón was punished with three days of house arrest, and forced to remove the offending line from the play.
By the time Lope de Vega died in 1635, Calderón was recognized as the foremost Spanish dramatist of the age. Calderón had also gained considerable favour in the court, and in 1636-1637 he was made a knight of the order of Santiago by Philip IV, who had already commissioned from him a series of spectacular plays for the royal theatre in the newly built Buen Retiro palace.
On May 28 1640 he joined a company of mounted cuirassiers recently raised by Gaspar de Guzmán y Pimentel, Count-Duke of Olivares, took part in the Catalonian campaign, and distinguished himself by his gallantry at Tarragona. His health failing, he retired from the army in November 1642, and three years later was awarded a special military pension in recognition of his services in the field.
His biography during the next few years is obscure. His brother, Diego Calderón, died in 1647. A son, Pedro José, was born to Calderón and an unknown woman between 1647 and 1649; the mother died soon after. Calderón committed his son to the care of his nephew, José, son of his brother Diego. Perhaps for reasons relating to these personal trials, Calderón became a tertiary of the order of St Francis in 1650, and then finally joined the priesthood. He was ordained in 1651, and became a priest at San Salvador at Madrid. According to a statement he made a year or two later, he decided to give up writing secular dramas for the commercial theatres.
Though he did not adhere strictly to this resolution, he now wrote mostly mythological plays for the palace theatres, and autos sacramentales--one-act allegories illustrating the mystery of the Eucharist--for performance during the feast of Corpus Christi. In 1662 two of Calderón's autos, Las órdenes militares and Mística y real Babilonia, were the subjects of an inquiry by the Inquisition; the former was censured, its manuscript copies confiscated, and remained condemned until 1671.
Calderón was appointed honorary chaplain to Philip IV in 1663, and continued as chaplain to his successor. In his eighty-first year he wrote his last secular play, Hado y Divisa de Leonido y Marfisa, in honor of Charles II's marriage to Maria Luisa of Orléans. Notwithstanding his position at court and his popularity throughout Spain, his closing years seem to have been passed in relative poverty.
Calderón initiated what has been called the second cycle of Spanish Golden Age theatre. Whereas his predecessor, Lope de Vega, pioneered the dramatic forms and genres of Spanish Golden Age theatre, Calderón polished and perfected them. Whereas Lope's strength lay in the sponteneity and naturalness of his work, Calderón's strength lay in his capacity for poetic beauty, dramatic structure and philosophical depth. Calderón was a perfectionist who often revisited and reworked his plays, even long after they debuted. This perfectionism was not just limited to his own work: many of his plays rework existing plays or scenes by other dramatists, improving their depth, complexity, and unity. (Many European playwrights of the time, such as Molière, Corneille and Shakespeare, reworked old plays in this way.) Calderón excelled above all others in the genre of the "auto sacramental", in which he showed a seemingly inexhaustible capacity to giving new dramatic forms to a given set of theological constructs. Calderón wrote 120 "comedias", 80 "autos sacramentales" and 20 short comedic works called "entremeses".
Pedro Calderón appears in the 1998 novel The Sun Over Breda by Arturo Perez-Reverte, which takes up the assumption that he served in the Spanish Army at Flanders and depicts him during the sack of Oudkerk by Spanish troops, helping the local librarian save books from the library in the burning Town Hall.