daughter of Edward Irving, and was from 1851 to 1866 a deacon in the Irvingite church. His name was removed from the church register before 1872.
After his marriage Gardiner settled in London, and while maintaining himself largely by teaching began to study EngHsh history. He was admitted to read in the British Museum on 8 Nov. 1856, and to the Record Office on 1 July 1858. His desire from the first was to write the history of the Puritan revolution, but he thought it necessary to begin by studying the reign of James I. 'It seemed to me,' he afterwards wrote, 'that it was the duty of a serious inquirer to search into the original causes of great events rather than, for the sake of catching at an audience, to rush unprepared upon the great events themselves.' The first-fruits of these researches were some articles published in 'Notes and Queries' during 1860, which explained the causes of the quarrel between James and his parliament and threw fresh hght on his policy towards the Roman catholics. Next, at the instigation of John Bruce (1802-1869) [q. v.], then director of the Camden Society, Gardiner edited for that body in 1862 a volume of reports and documents, entitled 'Parliamentary Debates in 1610.' In 1863 the first instalment of his history appeared, 'A History of England from the Accession of James I to the Disgrace of Chief Justice Coke, 1603-1616' (2 vols.). This was followed in 1869 by 'Prince Charles and the Spanish Marriage' (2 vols.). The reception of these books would have discouraged most men. About a hundred copies of the first work were sold, but most of the edition went for waste paper ; the second had a circulation of about 500, but did not bring the author anything. Gardiner persevered, and his third instalment, published in 1875, 'A History of England under the Duke of Buckingham and Charles I, 1624-1628' (2 vols.), paidits expenses. The fourth instalment, 'The Personal Government of Charles I' (2 vols. 1877), and the fifth, 'The Fall of the Monarchy of Charles I' (2 vols. 1882), produced some small profit. This portion of his history was reissued under the title of 'History of England, 1603-1640' (10 vols. 1883-4). The next portion of his history consisted of three volumes issued separately in 1886, 1889, and 1891, under the title of 'The Great Civil War,' followed finally by three other volumes, called 'The History of the Commonwealth and Protectorate,' in 1895, 1897, and 1901. The regular production of these sixteen volumes was made possible by Gardiner's methodical and strenuous industry. He examined systematically every source of information. He studied in the archives of different European capitals papers illustrating the diplomatic history of the Stuart period, and he presented to the British Museum two volumes of transcripts which he had made at Simancas, besides other documents copied elsewhere (Add. MSS. 31111-2). For many years he lived in Gordon Street, within easy reach of the British Museum and the Record Office ; subsequently, while residing in succession at Bromley, Bedford, and Seven-oaks, he came up to London nearly every day to work in those two storehouses of historical materials. His chief recreation was cycling, and in his holidays he familiarised himself with the battle-fields of the English civil war and followed the campaigns of Montrose in Scotland and of Cromwell in Ireland. During the greater part of the period in which the history was produced Gardiner was actively engaged in teaching. From 1872 to 1877 he was a lecturer at King's College, London, and in 1877 he succeeded John Sherren Brewer [q. v.] there as professor of modern history. Between 1877 and 1894 he lectured regularly for the Society for the Extension of University Teaching in London. He also taught at Bedford College (1863-81) and in private schools near London, and lectured at To3nibee Hall.
Gardiner liked teaching and was an admirable popular lecturer. He used no notes and spoke in a simple, conversational manner, arranging his facts very clearly, and weaving the different threads of the subject into a connected whole with remarkable skill. His elevation of tone and his breadth of view made his verdicts on statesmen and his exposition of principles impressive as well as convincing. The six lectures on 'Cromwell's Place in History,' given at Oxford in 1896, are a good example of his style, though they are not printed exactly as they were delivered, because they were not written till he was asked by his audience to publish them.
Besides teaching, Gardiner found time to write a number of historical text-books. To the 'Epochs of English History,' published by Longmans, he contributed in 1874 'The Thirty Years' War,' and in 1876 'The Puritan Revolution' (15th impression 1902). He was the author of an 'Outline of English History for Children' (1881 ; new edit. 1901) and of a 'Student's History of England' for the