Who is Julius Enderby: from The Caves of Steel and what is their importance?

Enderby is the Commissioner of Police in New York City. He is the only human present right after the murder of Dr. Sarton. He is an old college friend of Lije Baley's, and a very competitive and driven man. He is friendly with the Spacers as well, although he has Medievalist tendencies. He wears spectacles, which are considered Old worldly, and has a window in his office, which is odd and rare for any office inside the City.