How and why did polite manners and etiquette develop?

The term "polite" already suggests that these rules of conduct developed at court. But were the royal and princely courts of the Middle Ages really the origin of what we today call good manners or etiquette? And why did this develop into this particular era in human history? Why not before or later? Currently, politeness…

If the host is planning a confirmation dinner at a restaurant, do they bring table decorations and flowers to the restaurant beforehand so that the tables can be decorated with them?

My son is about to be confirmed, and after church, 14 of us are going to an upscale restaurant with a medieval tower room for lunch. Afterwards there is coffee and cake at home. I'm in the process of putting together table decorations for home, but I don't want to buy super expensive decorations for…