By about 1600, though, it had become the norm in English to capitalize the first word of a sentence. In other respects, though, English documents of the 16th and 17th centuries differ strongly from our own practice, with erratic and typically effusive capitalization: writers felt free to capitalize any word they felt like capitalizing. Even in the early 18th century, we find such a distinguished writer as Jonathan Swift capitalizing every single noun -- a practice which is still normal in written German today.

By about the middle of the 18th century, capitalization practice had largely settled down to approximately the norms we follow today.

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[ In America a movement against this use of capitals appeared during the latter part of the eighteenth century. In Jefferson’s first draft of the Declaration of Independence nature and creator, and even god are in lower case. During the 20’s and 30’s of the succeeding century, probably as a result of French influence, the movement against the capitals went so far that the days of the week were often spelled with small initial letters, and even Mr. became mr. Curiously enough, the most striking exhibition of this tendency of late years is offered by an English work of the highest scholarship, the Cambridge History of English Literature. It uses the lower case for all titles, even baron and colonel before proper names, and also avoids capitals in such words as presbyterian, catholic and christian, and in the second parts of such terms as Westminster abbey and Atlantic ocean.] H.L. Mencken, The American Language