The Indian Emperor was published in 1667. It is a tragedy in rhyme, intended for a sequel to Howard's Indian Queen. Of this connexion notice was given to the audience by printed bills, distributed at the door; an expedient supposed to be ridiculed in the Rehearsal, where Bayes tells how many reams he has printed, to instil into the audience some conception of his plot.

In this play is the description of night, which Rymer has made famous by preferring it to those of all other poets.

The practice of making tragedies in rhyme was introduced soon after the restoration, as it seems, by the earl of Orrery, in compliance with the opinion of Charles the second, who had formed his taste by the French theatre; and Dryden, who wrote, and made no difficulty of declaring that he wrote, only to please, and who, perhaps, knew that by his dexterity of versification he was more likely to excel others in rhyme than without it, very readily adopted his master's preference. He, therefore, made rhyming tragedies, till, by the prevalence of manifest propriety, he seems to have grown ashamed of making them any longer.

To this play is prefixed a very vehement defence of dramatick rhyme, in confutation of the preface to the Duke of Lerma, in which sir Robert Howard had censured it.

In 1667, he published Annus Mirabilis, the Year of Wonders, which may be esteemed one of his most elaborate works.

It is addressed to sir Robert Howard by a letter, which is not properly a dedication; and, writing to a poet, he has interspersed many critical observations, of which some are common, and some, perhaps, ventured without much consideration. He began, even now, to exercise the domination of conscious genius, by recommending his own performance: "I am satisfied that as the prince and general [Rupert and Monk] are incomparably the best subjects I ever had, so what I have written on them is much better than what I have performed on any other. As I have endeavoured to adorn my poem with noble thoughts, so much more to express those thoughts with elocution."

It is written in quatrains, or heroick stanzas of four lines; a measure which he had learned from the Gondibert of Davenant, and which he then thought the most majestick that the English language affords. Of this stanza he mentions the incumbrances, increased as they were by the exactness which the age required. It was, throughout his life, very much his custom to recommend his works, by representation of the difficulties that he had encountered, without appearing to have sufficiently considered, that where there is no difficulty there is no praise.

There seems to be, in the conduct of sir Robert Howard and Dryden towards each other, something that is not now easily to be explained[101]. Dryden, in his dedication to the earl of Orrery, had defended dramatick rhyme; and Howard, in the preface to a collection of plays, had censured his opinion. Dryden vindicated himself in his Dialogue on Dramatick Poetry: Howard, in his preface to the Duke of Lerma, animadverted on the vindication; and Dryden, in a preface to the Indian Emperor, replied to the animadversions with great asperity, and almost with contumely. The dedication to this play is dated the year in which the Annus Mirabilis was published. Here appears a strange inconsistency; but Langbaine affords some help, by relating that the answer to Howard was not published in the first edition of the play, but was added when it was afterwards reprinted; and, as the Duke of Lerma did not appear till 1668, the same year in which the dialogue was published, there was time enough for enmity to grow up between authors, who, writing both for the theatre, were naturally rivals.

He was now so much distinguished, that, in 1668[102], he succeeded sir William Davenant as poet laureate. The salary of the laureate had been raised in favour of Jonson, by Charles the first, from a hundred marks to one hundred pounds a year, and a tierce of wine; a revenue, in those days, not inadequate to the conveniencies of life.

The same year he published his Essay on Dramatick Poetry, an elegant and instructive dialogue; in which we are told, by Prior, that the principal character is meant to represent the duke of Dorset. This work seems to have given Addison a model for his Dialogues upon Medals.