Persuasion in Kingdom Come Deliverance is covered on this page.
Sometimes you need powers of persuasion to achieve your goals. When talking to people, you can often choose what kind of impression you want to make on them.
eYou can simply use Speech, which, however, is influenced by the reputation you have at that moment with the person you're talking to.
In the middle ages, social status was paramount, so the quality of your attire and how well-groomed you are, together with your reputation, can make a big difference to how people respond to you.
If you look dangerous, people will be afraid to cross you and will also be more willing to assign risky tasks to you. That's influenced mainly by your Strength and the deterrent effect of your weapons and equipment, but other things are also taken into account, such as blood stains on your clothes.
You can sometimes rely on money to do the talking for you. You just have to agree on a persuasive sum. Bribing people works in the same way as shopping ;see Trade and Haggling).
In special cases, you can try any of Henry's other skills, e.g. Horsemanship.
It's not only the manner of persuasion that's important, but also the specific offer, because sometimes it's not enough just to choose according to your highest characteristics. You have to really read what Henry is going to say!