amblesideonline.org and gutenberg press are good sources of orginal texts, very handy for Kindle owners as most of it is free.
I've found that researching a historical period, and then reading a fiction written in that period really seems to bring history "alive" for DS. The social context of events is important for children to understand. We try and do the same with English translations of foreign authors when learning about other countries.
Their vocabulary is broadened far more if they have access to the original versions of books than the modern, pc edited stuff so their literacy skills improve. Thinking about how language has developed, and words and phrases have changed over time makes story time more interesting and actually promotes diversity in a funny sort of way.
I'm also honest enough to say I LOVE the incredulous look on DS's face at times at some old stereotypes "Mum - he did NOT just say that!", "That's just wrong to talk about someone like that isn't it mum?", "They are idiots, everyone knows girls can play football!" etc, etc.
It's good for kids to think about and articulate why some societal attitudes are wrong, consideration for others isn't a skill you can spoon feed, it needs to become an integral part of their character. A bit of righteous indignation as Anne is put to wash up yet again while the boys do "manly" stuff doesn't do any modern child any harm.
I have a cousin called Titti - and she's so fierce I DARE anyone to snigger at her name to her face!