You can watch the recent contributions on youtube - the last three contributions took a look at the Irish in the Napoleonic time, and I admit - highly enjoyable and I learned a lot.
And I would fully agree that being drunk wasn't specific for Irish troops but for lots of Napoleonic soldiers - there are numerous incidents were whole units were unfit to fight due to being dead drunk.
here the last link about Beresford.
Thanks Zach for those most enjoyable and informative series.
To follow up on @Hans - Karl Weiß ‘s assertion that drunkenness and it’s associated reduction in military efficiency was not exclusively an Irish or British sport. Here is an example from the so-called elite and therefore highly disciplined Chasseurs of the Guard from November 1805: “Despite the snow, which was falling in avalanches, the foragers of the companies (and there were many of them) found some excellent cellars of Hungarian wines. We drank of these to warm ourselves, to refresh ourselves, to dispel the tedium of being crammed and half-stifled in rooms when we could not move hand or foot; lastly we drank so much that if we had had to fire it muskets that night we should not have been able to handle our cartridges. . . . A benevolent spectator of this gigantic orgy, drinking next to nothing, I marvelled, without being dazzled, att the surprising capacity of some of the men, which was truly Gargantuan. On the following day, the 9th, during a long and fatiguing march, most of the men, being forced to lie down by the roadside, having no legs to follow their comrades, had sufficient proof that this wine was harmful rather than beneficial to the health” Memories of a Napoleonic Officer: Jean-Baptiste Barrès Page 70 Pen and Sword, Barnsley 2017