The satirical journal PNIS (the “Proceedings of the Natural Institute of Science”) has an article out on “Beards of War: Relationships between facial hair coverage and battle outcome in the U.S. Civil War“. This is of course the second in a series, because they had to build a dataset on beardedness first.
The answer: facial hair doesn’t seem to matter. Their table of overall standings by facial hair type is interesting. Looking only at the battles with clear wins and losses, the standings are as follows, sorted by win percentage:
| Facial hair type | Wins | Losses | Win percentage |
| Muttonchops with moustache | 6 | 0 | 1.000 |
| Friendly muttonchops | 14 | 7 | 0.667 |
| French cut | 26 | 21 | 0.553 |
| Moustache | 27 | 22 | 0.551 |
| Chin curtain | 7 | 6 | 0.538 |
| Van Dyke | 36 | 35 | 0.507 |
| Long beard | 65 | 65 | 0.500 |
| Short beard | 63 | 67 | 0.485 |
| Muttonchops | 8 | 9 | 0.471 |
| Clean shaven | 14 | 22 | 0.389 |
| Goatee | 1 | 5 | 0.167 |
What jumps out to me immediately from this table is that the styles at the top and bottom tend to be the rarer styles. But this is exactly what you’d expect even if facial hair has no effect on battle ability, just because these are smaller samples.
A few possible confounders that weren’t addressed:
- Facial hair style could be correlated with age. Perhaps older generals win more battles. Or less. (And maybe there’s some correlation with testosterone levels. Who knows?)
- Facial hair style is correlated with US region (i. e. North vs South). The first paper in the series observes that there are differences in facial hair styles (with the Union being more bearded). The Union won more battles than the Confederacy according to the National Park Service data set that was used as the list of battles (the final count is Union 197, Confederacy 123, Inconclusive 63) so this could be an issue.
God plays dice 