I believe it was in this book: https://www.amazon.com/Masterminds-Programming-Conversations...

While not a history book, per se, "Masterminds of Programming: Conversations with the Creators of Major Programming Languages" [1] is a pretty great read. You can get a ton of historical context from reading what the language designers were thinking when they created their languages.

[1] http://www.amazon.com/Masterminds-Programming-Conversations-...

Thanks for the great resource!

Similar interviews are in the following book from 2009. (I am not related to the book, I just read it years ago)

Masterminds of Programming: Conversations with the Creators of Major Programming Languages

http://www.amazon.com/Masterminds-Programming-Conversations-...

[...] exclusive interviews with the creators of several historic and highly influential programming languages [...]

• Adin D. Falkoff: APL

• Thomas E. Kurtz: BASIC

• Charles H. Moore: FORTH

• Robin Milner: ML

• Donald D. Chamberlin: SQL

• Alfred Aho, Peter Weinberger, and Brian Kernighan: AWK

• Charles Geschke and John Warnock: PostScript

• Bjarne Stroustrup: C++

• Bertrand Meyer: Eiffel

• Brad Cox and Tom Love: Objective-C

• Larry Wall: Perl

• Simon Peyton Jones, Paul Hudak, Philip Wadler, and John Hughes: Haskell

• Guido van Rossum: Python

• Luiz Henrique de Figueiredo and Roberto Ierusalimschy: Lua

• James Gosling: Java

• Grady Booch, Ivar Jacobson, and James Rumbaugh: UML

• Anders Hejlsberg: Delphi inventor and lead developer of C#

(Neither the The A-Z of Programming Languages nor Masterminds of Programming interviewed Niklaus Wirth (Pascal, Oberon, etc.).)