So far I've read several biographies. Of those, the two people whose lives have engrossed me the most were Aimee Semple McPherson and John Donne. I guess it's because they both were xtians and both had convoluted edges about their lives. By different routes, they both ended up being preachers.
Back in 2004, the Royal Society of Literature awarded John Stubbs the Jerwood Award for his biography of John Donne. I must say that Stubbs definitely earned every bit of it. His book was very well written and conveyed a vivid picture of John Donne's variegated life and the times in which he lived, during the transition from Elizabethan to Jacobean England.
The book is now out in an American edition from W.W. Norton. As I recall, there was an earlier edition printed in the U.K. under a somewhat different title.
But I would like to point out a quote, given at the start of chapter 17 in the book. There Stubbs is quoting Donne from his Sermons (vol.2, Nº13, page 280, 19th December 1619):
The true Church, Donne insisted, "Loves the name Catholique". If one followed "Those universall, and fundamentall doctrines, which in all Christian ages, and in all Christian Churches, have been agreed by all to be necessary to salvation…then thou art a true Catholique."
The emphasis was mine. Of course, being a Protestant, Donne had a larger and more universal idea in mind when here he used the word "Catholique", certainly not in the more limited sense that nowadays we mean by the term "Roman Catholic". But what is especially interesting to me is Donne's use of the word "fundamentall", by which he was referring to something that exists at the very core of things—those doctrines that simply cannot be let go of. Because if someone lets go and departs from them, he essentially has ceased being part of the Church and has become something altogether different.
For if there is nothing that is genuinely fundamental, and everything can be subtracted out, with absolutely everything being negotiable, then surrender is really all that is left over. Nevertheless, it does seem that the word "fundamental" does go back a long ways and is not merely something that got started back in the 1920s.
I highly recommend John Stubb's book.