William Blake illustratedParadise Lost more often than any other work byJohn Milton, and illustrated Milton's work more often than that of any other writer. The illustrations demonstrate his critical engagement with the text, specifically his efforts to redeem the "errors" he perceived in his predecessor's work.

The Thomas set
The paintings of the Thomas set are each approximately 10 x 8.25 inches. They were commissioned by the Reverend Joseph Thomas at an unrecorded date, sometime before 1807. Although the sheets were trimmed at some time, obliterating the date from several, some still retain the date of 1807, establishing the year of their completion. Thomas' grandson inherited them from his father, and sold them atSotheby's in 1872. By 1876 they were in the collection of Alfred Aspland, who by 1885 took them to Sotheby's again, dispersing the set among several buyers.Henry Huntington reunited the works in 1914, and today they are still in the collection of theHuntington Library.
The Butts set
The dimensions of the Butts set, also known as the "large set", are 19.5x15.5 inches, nearly twice that of the Thomas set. Dated 1808, they were commissioned from Blake by his patronThomas Butts, who also commissioned many paintings on biblical themes from Blake. In the early 1850s, Butts' son Thomas Butts Jr. offered the individual paintings for sale at several auctions, resulting in the dispersal of the set. Today it remains divided between four museums. Nine of the paintings were sold at Messrs. Foster in 1853 to J. C. Strange, passing through several other hands before they were acquired by theMuseum of Fine Arts, Boston, their present owner. The other three were sold to one "Fuller" at an unknown date, from whom they passed to H.A.J. Munro. Munro further complicated matters by selling the three paintings to separate buyers atChristie's in 1868. No. 1 was acquired by theVictoria and Albert Museum in 1869, No. 2 byHenry Huntington in 1916, and No. 10 by theHoughton Library in 1966.
The Linnell set
The Linnell set is incomplete – it contains onlySatan Watching the Endearments of Adam and Eve,The Creation of Eve andMichael Foretells the Crucifixion. These are exactly the same as their corresponding entries in the Butts set in both size and composition, the major difference being their loose handling of the watercolor. Like the Linnell set ofWilliam Blake'sIllustrations of the Book of Job, these were commissioned by Blake's patronJohn Linnell, and traced by Linnell from the Butts set. An entry in Linnell's journal dates the commission to 9 May 1822. CurrentlySatan Watching the Endearments of Adam and Eve andThe Creation of Eve are in the collection of theNational Gallery of Victoria, andMichael Foretells the Crucifixion is in the collection of theFitzwilliam Museum.

There are twelve plates in each of theParadise Lost sets, one for each of the books in the poem. While some of these, such asSatan, Sin and Death: Satan Comes to the Gates of Hell, depict specific scenes from the epic; others, such asSatan Watching the Endearments of Adam and Eve, are syntheses of several scenes.[1] In the latter case, Blake employed visual barriers to separate the elements from different scenes, such as the arc of the bower inSatan Watching the Endearments of Adam and Eve.[2]
InBlake's mythology,Albion's fall from a divineandrogyny to a sexual nature divides him into the Four Zoas, their spectres (representative of hypocritical morality), and their emanations (female halves). In theParadise Lost illustrations, Adam is analogous to the fallenAlbion, Satan to Adam'sSpectre, and Eve to Adam'semanation.[3]