Who is Julian Black from The Modigliani Scandal and what is their importance?

Julian Black is an old friend of Peter's from their school days. He is opening an art gallery, but he refuses to handle Peter's artwork because he thinks his paintings are overpriced and not selling very well.

Julian is married to Sarah, who is the daughter of Lord Cardwell. His marriage, however, is strained because he is living off of his wife and her father's money. Lord Cardwell gave Julian the money to open the art gallery, but the money wasn't quite adequate to do it properly. When Julian learns about the lost Modigliani, he decides to try to find the picture, knowing that Lord Cardwell will put up the money to buy it if he finds it.