king after king was murdered and central authority barely existed. It was easily overrun by the Konbaung armies in 1784–1785. Nyaungyan restoration While the interregnum that followed the fall of Pagan Empire lasted over 250 years (1287–1555), that following the fall of Pegu was relatively short-lived. One of Bayinnaung's sons, Nyaungyan, immediately began the reunification effort, successfully restoring central authority over Upper Burma and Shan States by 1606. Nyaungyan's successor Anaukpetlun had restored Bayinnaung's empire (except Siam and Lan Xang) by 1624. Upper Burma and nearer Shan states (1597–1606) After the fall of Pegu in December 1599, Lower Burma was in utter chaos, and politically fragmented among Toungoo, Prome, Arakanese/Portuguese Syriam and Siamese Martaban. In Upper Burma, however, Nyaungyan, viceroy of Ava, had been quietly consolidating his holdings since 1597. Though nominally loyal to Nanda, Nyaungyan provided no support to his overlord. In October 1599, just as Toungoo and Arakanese were laying siege on Pegu, Nyaungyan sent a force to reclaim Mohnyin, Mogaung, and Bhamo. After Pegu fell, Nyaungyan declared himself king on 25 February 1600. Nyaungyan then systematically reacquired nearer Shan states. He captured Nyaungshwe in February 1601, and the large strategic Shan state of Mone in July 1603, bringing his realm to the border of Siamese Lan Na. In response, Naresuan of Siam marched in early 1605 to attack Mone but died at the border in April after which Siam ceased to be a military concern to Burma. In early 1606, his 7,000-strong forces took Theinni, Thibaw and Momeik but the king died during the campaign on 3 March 1606. Lower Burma (1607–1613) With Upper Burma securely under his control, Nyaungyan's successor Anaukpetlun marched south. His 14,000-strong land and naval forces sacked Prome on 13 July 1608 after a bloody siege of eight months. His 12,000-strong forces then attacked Toungoo, then ruled by his cousin, Natshinnaung, in August 1610. After a siege of 23 days, Natshinnaung agreed to become a vassal on 4 September 1610. But Natshinnaung was deeply unhappy with his reduced status, and secretly invited de Brito of Syriam to attack Toungoo. In July 1612, Syriam and Martaban forces ransacked the city for ten days, and left, taking Natshinnaung to Syriam. In response, Anaukpetlun's army of 13,000 (700 horses, 60 elephants) left Ava for Syriam on 26 December 1612. A flotilla of 80 war boats and 30 cargo boats (3,000 men) was also sent down the