While other scholars had assumed that the Mahavamsa had been assembled from borrowed material from Indian Pali sources, Geiger hypothesized that the Mahavamsa had been based on earlier Sinhala sources that originated on the island of Ceylon.
Sementara para sarjana lain berasumsi bahwa Mahavamsa telah dikumpulkan dari bahan pinjaman dari sumber Pali India, Geiger berhipotesis bahwa Mahavamsa telah didasarkan pada sumber Sinhala awal yang berasal dari pulau Ceylon.