The Question I wish to ask, is regarding the use of famous people or characters dead or alive in parts of your novel. Do you need to seek their permission or can you use some kind of Disclaimer in the front of your novel. I would like to know your thoughts and opinions on this and if there is any legal rulings both in the USA and UK.
It depends on how long they've been dead, 70 years after someone's death everything about them enters the public domain which means you can do whatever you like with them.
It is polite to ask permission and not doing so could land you in all sorts of trouble if they think the portrayal is unflattering. I only have real people in my sixth book in the series so I'm not going to start worrying about it until I've published book four. Lol
You just have to beware of libel laws. Using living persons is most dangerous, the recently deceased less so and the long-dead least problematic, though descendants can still sue.
If your character possesses well known and previously documented character traits, and performs factual actions, you should have few problems. There is a defence in UK libel law of 'fair comment' (not sure about the US). I'd have thought it's only if you diverge from the generally accepted view of that person (unless you can back up your assertions with hard fact) that problems are likely to arise.
It's difficult for me to be completely certain about this since I've only used real people who were alive in the early 19th century, many of whom make regular appearances in historical fiction anyway. With those who rarely appear in print I've stuck to my impression of their characters from non-fiction accounts I've read.
No problems so far ;)