
At the weekend I was lucky enough to be involved in a WW2 convoy battle wargame at the Western Approaches HQ at Derby House in Liverpool, from which the Battle of the Atlantic was commanded. The museum is an amazing place – it seems that it was left almost untouched until it opened as a museum a few years ago, and most of the place, right down to door signs and telephony kit, seems to be original. The re-built wall chart of the Atlantic is pictured above. I was commander of a Black Swan class sloop – a lovely new ship, purpose-built as a convoy escort – and encountered a surfaced U-boat, played by a RN Submarine Warfare Officer, almost immediately.
This wasn’t just a modern wargame; it was a re-enactment of the game devised by the Western Approaches Tactical Unit (WATU) during the war, and used by them both to develop tactics and to train escort commanders in applying them. The full records are lost, but the game has been re-created in superb, faithful detail by Kit Barry, who tells the full story. (Paul Strong’s article is also worth reading.)
The way it works is this. Each escort and each U-boat has a commander, and they can only communicate by radio. Each commander has a go-between who communicates their intentions to, and implements their decisions on, the gaming floor. The commanders do not see this; rather, once per turn, they are given first a glimpse of their part of the floor through a covered screen with a peep-hole, and then a list of the bearings and ranges of what they have seen. I loved this. All animals should be allowed to express their natural behaviour, and doing mental trigonometry to work out a course to intercept is certainly mine.
The original game was mostly run by WRNs, and by all accounts WATU was a strikingly diverse set-up for its time, training commanders from all over the British Empire, with its ethos now captured by the “Derby House Principles” – diversity not just for its own and higher purposes, but to avoid group-think and generate thoughts from out of the box.

A maths professor may not be an obviously diverse inclusion, but I was the only one there, and I was certainly thinking. I’m not an experienced wargamer, and wargaming is often said to be more art than science, but I was considering it as a scientist. The game is engineered to work, to approximate reality, and to be robust and replicable. But I do wonder whether any of a game’s outcomes are artefacts of the way the game is played – the physical model, the rules, the parameters, the probabilities. First, is there anything which might systematically skew the game away from reality? Second, how normal is the outcome – how big is the spread of possible outcomes, where is our game in that spread, and does the spread coincide with the distribution in reality? In fact I think this game was pretty good – perhaps because it was based on a real game, honed over months and years, and played many times, in earnest.
A more subtle point, for the psychologist on the team, is whether or not people’s game personalities are systematically different from their real-life ones. Concerning modern strategic gaming, a young analyst made a point to me over dinner which seemed crucial: not only are participants less risk-averse than they might be in reality when their and others’ lives are at stake, but they become much more so close to the end of the game, when they will take great risks to “win”. (Exactly the same thing happens towards the end of probability forecasting tournaments, using Brier or log scores, which are only “proper” – rewarding forecasts which match beliefs – as long as the reward is proportional to the score, rather than winner-takes-all.) In reality, of course, the game has ended at an arbitrary moment, and the world moves on – with continuing decision-making within it.
Our own game, too, only ran for a fixed time. By then, I had my target U-boat chased down, depth-charged, damaged, surfaced, under my six 4″ QF guns at 300 yards on my port beam, and had hit it twice. At which point, damnit, the game ended. Gutting. But perhaps I was getting too into it. As my kids said later, “Dad, you almost sank a pretend U-boat in a pretend game.”
Note added 12/5/2023: Kit Barry has posted a fuller account at PAXsims.