England in Medieval Times

The city lords wanted to attract merchants more because they paid taxes to them, which was collected by the sheriff. The system was prone to corruption because of illiteracy, so people demanded for charters that saved them from fraudulent sheriffs and provided them with law courts.
There also was no proper sewage system in medieval cities because people would throw their bathroom waste and garbage right onto the streets which gave rise to many diseases. This increased rats in medieval cities which gave rise to bubonic plague causing the Black Death which lasted one year (1348-49). Water was also polluted because it was contaminated with toilet waste both by the city residents and the villagers. People were ignorant of hygiene and cleanliness. Hence, life expectancy was also very short as diseases were common.
Cities would be on a curfew but there was no police force to arrest the law breakers. Raids were common. Houses would catch fire every now and then since they were made of wood. The land was costly. These were some immediate crises that informed the creation of medieval cities.