John Cotton (1584-1652) was a key figure in the English Puritan movement in the first half of the seventeenth century, a respected leader among his generation of emigrants from England to New England. This volume collects all known surviving correspondence by and to Cotton. These 125 letters - more than 50 of which are here published for the first time - span the decades between 1621 and 1652, a period of great activity and change in the Puritan movement and in English history. Now carefully edited, annotated, and contextualized, the letters chart the trajectory of Cotton's career and revive a variety of voices from the troubled times surrounding Charles I's reign, including those of such prominent figures as Oliver Cromwell, Bishop John Williams, John Dod, and Thomas Hooker, as well as many little-known persons who wrote to Cotton for advice and guidance. Among the treasures of early Anglo-American history, these letters bring to life the leading Puritan intellectual of the generation of the Great Migration and illustrate the network of mutual support that nourished an intellectual and spiritual movement through difficult times.