Pratap Malla (1624–74 A.D.) was King of Kantipur from 1641 until his death in 1674. He attempted to unify Kathmandu Valley by conquering Lalitpur and Bhaktapur, but failed in the effort. He was successful in extending and securing the borders of Kantipur and was responsible for the monopoly over trade with Tibet. The resulting prosperity was responsible for the construction of majority of the buildings around Durbar Square during his reign. His reign is seen as a cultural and economical high point of the Malla dynasty.