For the past 1,700 years the sacred Tooth Relic of Gautama Buddha was a possession of the ruling king/dynasty of that period, whosoever possessed this was acknowledged as the rightful ruler of Lanka and whoever won the throne usually came to possess it.
The possession of the tooth relic alone was however not sufficient for the general turned king; Don John Wimaladharmasurya, but the 'royalty' of Mahapatabandige Donna Catherina Kusumasanadevi.