Although he had finally conquered Siam, he still needed to deal with the middle Tai country. King Mekuti of Lan Na had allied himself with his old rival Setthathirath of Lan Xang. On 23 October 1564, Bayinnaung himself led five massive armies (64,000 men, 3600 horses, 330 elephants) and began a two-pronged invasion of Lan Na. The levies hailed from all over the empire, including Siam whose troops were led by Ramesuan, the former crown prince of Siam. The massive show of force worked. When four southern armies showed up at Lamphun, 20 km south of Chiang Mai, on 25 November 1564, the commanders leading Chiang Mai's defenses simply fled the city. Mekuti now submitted, asking for forgiveness. Bayinnaung spared the broken king's life, and sent him to Pegu. The Burmese king then stayed in Lan Na for the next four months, administering the country. He appointed Queen Visuddhadevi, as the vassal ruler of Lan Na before leaving Chiang Mai on 10 April 1565 to deal with a serious rebellion in Pegu.