I didn't want to review each episode one-by-one -- that would take too much effort. So this will sum up the whole series.
It's magnificent! Three years and fifty-two episodes, every one of which is well-written, acted, and directed. Sure, some are better than others, but in its totality there is almost nothing like it - - only the original "Upstairs Downstairs" can challenge it. The more recent "Downton Abbey" is definitely inferior. The much more recent "Seaside Hotel" has a lighter tone but covers some of the same ground, with fewer episodes and not quite so many compelling characters.
The main family, having five children, was well suited to the story of a middle class family living through six years of war. We feel for all of them. Five of the young men go off to war with various results. All are realistic. We care about the struggles of the men and those left behind. We see how the "other half" lives via Sefton Briggs. We see the reactions of in-laws and friends. But in the end it is Edwin who is the main character.
To modern viewers (2023 and later) the filming quality may be an issue. Yes, it looks dated. No HDTV here. But the quality of the story more than makes up for that.
Minor criticisms: Tony and Robert are not as fully fleshed out as the others. Some of the dialog seems a bit unrealistic to me, as I can't imagine saying such revealing things to siblings. But that's just me.
A great strength is that many of the people who filmed this and wrote it lived through WWII. That brings an authenticity that later generations can never have. Almost every episode is absorbing.
Now, I'm an American, not a Brit. Ignoring that, there is another big appealing aspect for me in "A Family at War". I'm in this movie. No, not literally, but I am the newborn baby near the end. That's my cohort, and these people are my parents and grandparents. This series is like reliving their lives.
This is great history wonderfully told.
