TITLE: History of Morse theory.
QUESTION [8 upvotes]: How can I get good references which give many information about history of Morse theory? Now I am interested in how and who found that Hessian have a lot of data. Thank you for your helping!!

REPLY [2 votes]: I would suggest:

Morse Theory Indomitable by R. Bott  which talks about the development of Morse Theory 
Morse Theory by J.Milnor which describes the classical approach to Morse Theory and its applications.