John Leonard is a professor of English at Western University in Ontario, formerly the University of Western Ontario. He studied at Trinity College, Cambridge, took a master's at McMaster, and returned to Trinity for his doctorate. In 1984 he won a Junior Research Fellowship there. He has taught at Cambridge, Ottawa and Western, where he has been since 1987.
Leonard is not a novelist or poet. He is a scholar and editor of seventeenth-century English literature, and John Milton is his lifelong subject. His first book, Naming in Paradise (Clarendon Press, 1990), begins with Adam naming the animals. It follows how names and naming work in Milton's poem before and after the Fall, and it won a James Holly Hanford Award. His second major book, Faithful Labourers (Oxford University Press, 2013), is a reception history in two volumes. One covers style and genre and the other covers interpretative issues. Together they follow three centuries of argument about Paradise Lost, from 1667 to 1970.
Western News described Faithful Labourers as the longest single-author book ever written on the poem, and said it took Leonard fourteen years. In 2014 the Milton Society of America named him its Honored Scholar, a lifetime award. He is also a Fellow of the Royal Society of Canada and has won a teaching award at Western.
Start with the Penguin Classics Paradise Lost, which is the book listed here. Milton wrote the poem, and Leonard supplies the introduction and notes that help a first-time reader through its dense, allusive verse. Readers who want to see why Satan has divided critics for centuries can then go on to Naming in Paradise. Faithful Labourers is a large reference work, better for a library visit than a bedside table.