The first fortified settlements on the site of today's Warsaw were located in Bródno (9th/10th century) and Jazdów (12th/13th century). After Jazdów was raided by nearby clans and dukes, a new fortified settlement was established on the site of a small fishing village called "Warszowa". The Prince of Płock, Bolesław II of Masovia, established the modern-day city in about 1300 and the first historical document attesting to the existence of a castellany dates to 1313. With the completion of St John's Cathedral in 1390, Warsaw became one of the seats of the Dukes of Masovia and was officially made capital of the Masovian Duchy in 1413. The economy then predominantly rested on craftsmanship or trade, and the town housed approximately 4,500 people at the time.