I know a king has a lot of servants/people under him that each serve a different purposes such as a steward, standard bearer, a master of the hunt, etc. But if a king decides he wants to build a monument, or a tower, or something, who would he approach to get the job done? Essentially what would be considered the medieval version of a general contractor.
This is a pretty interesting question. The first person an English king would probably talk to would be someone from Parliament. English Kings were still under the Magna Carta for a good portion of the Medieval Ages. The King would need to get the approval for the funds, if he didn’t want to pay out of pocket, for the construction. A new tax, tariff or levy may have to be imposed. Tariffs on Wool exports was a common way to pick up extra revenue for England during the medieval ages.
There was a medieval version of engineers and architects. While their trade and understanding was a lot cruder than it is today, they still had a concept for certain things. Some of these medieval architects were a lot more skilled than others as well, so depending on the grandeur of the project, the King may even have a famous architect brought in. I’m not exactly sure of the name at the time for it.
One of the most famous medieval architects was actually the Englishman Saint James of Mark, responsible for the Tower of London.
These architects would assemble teams of skilled laborers, masons, stone and woodworkers from all over, again depending on the grandeur of the project. Local magistrates may have also helped with supplying manpower for the construction of these projects as well.