This article argues against unnecessarily ‘scientific’ rigour in determining sources. Source study originated in Quellenforschung, a study of classical texts that mined an extant work for information about lost sources but ignored the work's own textual and contextual dynamics. Early source studies of Shakespeare similarly focused on a single source and one simple relation between source and play. Like nineteenth-century classical scholars, they insisted on quantifiable evidence and treated echoes as separate phenomena, as if they had had no effect on one another in the original process of being remembered and reused. Source study had no role in interpretation. The only important questions were: exactly how similar is each source line to its proposed Shakespearian echo? How many echoes are there?

Many accounts of sources still proceed this way but I argue instead for a contextual approach that studies each echo in the context of the original source from which it came, the play in which it supposedly landed and the other echoes from that source. My example is the Queen's Men's play, King Leir (1585–7?), long recognized as the primary source for Shakespeare's King Lear (1604/5). As critics continue to discover, the old play is the origin of many of its lines but the larger relationship between Shakespeare and Leir still remains to be examined. The following article collects all the Leir echoes together and adds a few, in order to see what Shakespeare borrowed from Leir.

In an often-quoted judgement, Charles Lamb noted that Shakespeare’s Richard II took hints from, but ‘scarce improved’ on, ‘the reluctant pangs of abdicating Royalty’ in Marlowe’s Edward II. But was Shakespeare in fact trying to ‘improve’ on Marlowe when he created his own ‘weak king’ in Richard II? Or was he doing something else? This paper re-examines Shakespeare’s play as a more complicated response to Edward II that reveals dynamic tensions between the two playwrights. Bertolt Brecht’s modern response to Marlowe in his 1922 Edward II provides a useful introductory comparison. Brecht seems to have been drawn to Marlowe’s play not so much for its political as for its personal relevance, in particular for its portrayal of the doomed bond between Edward and Gaveston – the kind of bond Brecht had just written about in The Jungle. Brecht was indeed trying to improve on, or at least to outdo, Marlowe’s bleak play. With a ‘savage pessimism’, he rewrote Marlowe to create a world where, as his Edward says, ‘There is nothing in life besides the touch of men’s bodies, and even that is minimal and vain.’ What interests me about Brecht’s play however is that it is not only about the difficult closeness between two men but – as adaptation, collaboration, and partly cribbed translation – it is also the product of such closeness. Edward II was the first of the collaborative ventures that were to serve Brecht so effectively as catalysts for creativity throughout his career.