Donald McLean (1820-1877) was arguably the most influential figure in mid-19th century New Zealand history, playing a central role in relations between Māori and the Government during this tumultuous period.

McLean was a fluent Māori speaker and was a confident participant at the many Māori hui (meetings) he attended throughout the country. His influence in part maintained a large network of informants, and he relied on their regular reports for information about what was going on around the country. His work also took him on many expeditions to meet with Māori leaders, which he carefully documented in his diaries and notebooks. The papers, therefore, provide a particularly rich record of interactions between Government and Māori at this time.