My comment was getting far too long, so I brought it back here and expanded it:
I'm realising that the War has such a massive influence on my novel too, even though all the main story events take place afterwards.
Kate was a volunteer nurse/nursing auxiliary at a hospital in
Hugh came back from the war very much changed by his experiences, which is what ultimately led to Julia running away. He wasn't necessarily a nice man before (all that business with the maids), but afterwards he was definitely the wrong choice for Julia.
Julia lost her original home and close family in the war, which is why she was determined to marry one of the brothers and stay in her adopted home. Her parents died when their home was destroyed in an early bombing raid and her brother never came back from an RAF mission a little later on. Once she realised that Edward was unlikely to marry her, she could have gone after some other wealthy and/or titled chap, but she was too attached to the Peveril Estate and settled for Hugh.
Jumping back in the back story ;-) with everyone off doing their bit for the war effort there was no one to keep an eye on the young Edward and Julia, which is how they became so close as teenagers. Julia's school had been evacuated en masse to the estate, and Kate, wanting to keep at least one of her sons close, decided that there was no point sending Edward away to school when they had a perfectly good set of teachers lodging with them. Of course after the war Edward got into a lot of fights back at his regular boarding school when the other boys found out about that.
I could almost certainly come up with a lot of additional details about how farming and estate management changed both when the men went away, and when some of them came back, but that's a post for another day.
[ETA:] Of course! Brigit might well not be where she is if her adoptive parents hadn't decided to head back to England because of the war.
Alex, is that what you meant about telling more?