A new dynasty called Konbaung led by King Alaungpaya rose in Upper Burma to challenge the southern forces, and went on to conquer all of Upper Burma by January 1754. After Hanthawaddy's second invasion of Upper Burma failed in May 1754, the kingdom's leadership in self-defeating measures killed off the Toungoo royal family, and persecuted ethnic Burmans in the south, both of which only strengthened Alaungpaya's hand. In 1755, Alaungpaya invaded Lower Burma. Konbaung forces captured the Irrawaddy delta in May 1755, the French defended port of Thanlyin in July 1756, and finally the capital Pegu in May 1757.