Im currently reading through the second volume and focusing mostly on the historical chapters rather then his translations of works by the Sikh Gurus. The first volume (Which goes into detail about Guru Nanak Dev Ji) goes into some detail about the sources that he used to publish Volume 1 however as i read volume 2 I notice no citations or explanations of Macauliffe's sources.
anon ji
Keeping in mind that journals and library collections of scholarly writing on Sikhi, and Internet archives as we have available today, did not exist in the time of Macauliffe. Though scholarly writings and exegeses of the Vedas were collected throughout India, and could be found in the private libraries of the wealthy and the ashrams of well-supported monastic orders, nothing close to that was available to Macauliffe. Moreover, many of the treasured writings were destroyed when Sikh institutions were destroyed in the century following the Death of Guru Gobind Singh. What there was, rested with the Nirmala situated in Benares and in the private collections of individuals here and there. So Macauliffe - as you will discover when you read this article - employed a multifarious strategy of working with documents as he could access them, picking the brains of noted scholars of the day, hosting informal seminars to allow for debate. In the end he did what all talented historians do: he pulled out a synthesis and wrote the story from an interpretation of many, diverse perspectives, documents and traditions, a synthesis that seemed logically coherent and could be supported by the more credible data. Research does not proceed in a straight line from a to z and this article is the best account of how Macauliffe accomplished his final results. When I read this article I am astounded by his knack for organizing interdisciplinary teams of experts in one field or another to move a huge project forward. Today we call this collaborative inquiry and governments and foundations fund grants and think tanks to accomplish similar results.
http://www.sikhchic.com/history/max..._introduced_sikhi_to_the_englishspeaking_west
I think that if you want more detail you should feel completely free to contact Dr Nikky Guninder Kaur Singh, who would be accessible unless she is traveling for research purposes. This is where to start. Chair and Professor of Religion at the Department of Religious Studies, Colby College, Waterville, Maine, U.S.A.
p/s You should be aware that there is a subset of Sikh opinion that is critical of Macauliffe's work because of his reliance on Nirmala and Udasi scholars and sources such as Suraj Prakash and the Gur Bilases, which have a decided Vedic bias. On the other hand, his work was also acclaimed by scholars on the Singh Saba side of the scholarly community. My own take on this is that Macauliffe followed his instinct to use multiple sources to triangulate on a consensus view. Good luck!