The duo's later campaigns against Arakan (1545–1547) and Siam (1547–1549) however fell short. In both campaigns, Toungoo forces won all major open battles, and went on to lay siege to the capitals, Mrauk-U and Ayutthaya respectively. But they still had no answer to heavily fortified defenses equipped with Portuguese firearms, and had to retreat both times. Toungoo's own Portuguese supplied cannon had little impact on the walls of both capitals. Nor did they have enough manpower (19,000 and 12,000 troops respectively in the Arakanese and Siamese campaigns) for long-term sieges. Nonetheless, despite the setbacks, Tabinshwehti and Bayinnaung had by 1549 built up the largest polity in Burma since the fall of the Pagan Empire in 1287, stretching from Pagan in the north to Tavoy in the south.