History Alive! The Medieval World and Beyond is a textbook published by TCI. Unless you have access through teaching resources, I don't believe you'll be able to read any of the book online. If you do use the book in your course, why don't you contact the sales rep for possible login information. I've pasted a link to the web page in the Sources section for you. By the way, that web site has links to several enrichment resources that look very interesting and that you might want to check out.