The British Free Corps was a unit which fought for the Germans in WWII, against Russia, recruited from the ranks of POWs. One of them was one of the men we heard about, one of only four people convicted of high treason in Britain after WWII. I was fascinated to learn such a Corps existed in the first place; the internet tells me many of you may already know of it thanks to its use in various (fictional) books and movies.
I'd also been unaware of the Princess Alice, whose wreck on the Thames is still, to this day, the largest loss of life in a river accident in Britain. Nearly 700 people died, and that's an estimate. 640 tickets were sold for the day-trip to Kentish pleasure gardens, but no tickets were issued for the many children on board. Not everyone died - but most did. Even strong swimmers were scuppered by the site of the collision, in the outwash of one of Bazelgette's fancy new sewer outlets, by Creekwater/Barking Village, at the mouth of the Roding River.
Several things went obviously wrong, leading to its collision with a large outbound cargo ship. The helmsman got off at Gravesend and entrusted the ship to a Thames novice. The currents are strong and different around the mouth of the Roding, and confused by the sewer outlet.
But really, when it came down to it, the single biggest confusion which caused the accident was the law which, just at the beginning of that year, had switched which side of the Thames upstream and downstream vessels needed to stick to. It's like switching which side of the road traffic should drive on, but in a place where sufficient road signs just aren't possible. The Princess Alice was caught by currents, and the ship approaching her thought she was switching sides of the river, as per regulation changes, to let it by. Collision ensued.
Passing directions on the Thames - port to port - have never been altered since.