In January 1864.
Anthony Trollope's Can You Forgive Her?, the first of his Palliser novels, begins to appear in monthly parts in London. Trollope completes it on April 28 and the first volume is published as a book in September by Chapman & Hall. In April, The Small House at Allington concludes publication in the Cornhill Magazine and is published in book form by George Smith.
https://en.wikipedia.org/wiki/Can_You_Forgive_Her%3F
Can You Forgive Her? at PG:
https://gutenberg.org/ebooks/19500