The age of Tennyson is defined, for the purpose of the present volume, as extending from 1830 to 1870. The date selected as the beginning of the period needs no explanation; but perhaps the question may be asked why the age of Tennyson should be supposed to end more than twenty years before Tennyson died. The answer is twofold. First, I may plead the strong law of necessity. Sixty years, among the most fertile and varied in our literary history, could be compressed within the limits of a volume like the present only by completely changing the scale of treatment; and this again would have put it out of harmony with the other volumes of the series. But, secondly, about the year 1870 or before it there took place a change in the _personnel_ of literature, less complete perhaps than that which marked the beginning of the epoch, but still sufficiently remarkable. Among the historians, Macaulay was dead and Carlyle had done his work. Among the novelists, Dickens died in 1870, Thackeray seven years before, and Charlotte Brontë still earlier; while, though George Eliot survived till 1880, the only great work of hers which lies beyond the limits of the period is _Middlemarch_. Mill, who had been so long the dominant power in philosophy, died in 1873. The poets, Tennyson, Browning, Matthew Arnold and Rossetti, survived. In poetry however Arnold's voice was by this time almost dumb. Browning continued to produce copiously; but after _The Ring and the Book_ his style changed, and changed decidedly for the worse. Tennyson changed too, but in his case there was some gain to balance what was lost. The best of the younger poets, like William Morris and Swinburne, clearly show the influence of new ideals. The old order was changing, and new ambitions were beginning to sway men's minds. In short, if by the age of Tennyson we mean the period during which the influences which formed Tennyson and his contemporaries were dominant, we find that it came to an end long before Tennyson's life closed. Tennyson and Browning, Arnold and Ruskin, therefore, have to be treated as survivors into a new period. But it is obviously undesirable to split a man's work in two; and consequently, though my period ends at 1870, I have included a sketch of the later work of these men as well. I have very rarely treated only a part of a man's work. I have preferred to leave wholly to my successor those writers who, though they had begun to write before 1870, seem on the whole to belong rather to the period still current.