Kukui was an important element to indigenous Hawaiian agroforestry and retained some of its importance throughout Hawai‘i's history. We examine the historical ecology and trends of kukui, including a review of the ethnobotany. We use current and historical remote imagery to map kukui canopy on the five largest Hawaiian Islands. Kukui is still widespread through the state, being a significant component in many novel low-land forests. However, kukui is declining, having lost an average of ∼58% of total canopy cover over the last 70 years. Spatial trends suggest that kukui likely did not spread much following the large-scale shifts in Hawaiian socio-ecosystems that accompanied the arrival of colonial powers. We suggest that the footprint of kukui in Hawai‘i closely approximates the extent of indigenous agroforestry and forest alteration.