 De Beauregard was named governor by King Narai of Siam in the place of the Englishman, Samuel White.De Beauregard was part of the retreat of the French troops of De Bruant there, following the 1688 Siamese revolution.Large-scale attacks were launched on the two French fortresses in Siam, Bangkok and Mergui, and on 24 June, the French had to abandon their garrison at Mergui.