These days we think of livery as clothing that identifies a group of people as belonging together, both in colour and design. It has its origins in the custom of a medieval lord giving food and clothing to the people who served him. Clothes would have been given once a year and wine probably at Christmas, as well as food at various times of the year.
After a time, ‘livery’ came to signify just the clothing itself and not the food. Originally the colours were russet or blue, but, after a while, the clothes became part of an identification system at courts across Europe. Clerks wore blue, knights green and squires stripes. Household servants also wore stripes. It wasn’t just lords who did this; guilds also had their own liveries to identify their members.
Wearing a man’s livery meant that you were under his protection. With greater lords, the livery included their heraldic colours, which made it easy to identify their retainers. This was both a blessing and a curse, as it meant that most people were less likely to antagonise them, although it also made them the target of the retinue of a lord who might not be on the best of terms with their lord. It also meant that they were also easily recognisable if they committed a crime whilst wearing their livery. For the lord himself there were also benefits. The more men a lord had dressed in his livery, the more powerful, important and wealthy he seemed to everyone else.
Liveried retainers must often have committed crimes or caused problems, for Parliament tried on several occasions to introduce laws in order to have more control over them during the reign of Richard II. John of Gaunt argued, however, that dealing with a lack of discipline in his household was the responsibility of the lord and not the courts.
Chaucer, as a member first of the household of the Countess of Ulster and then of her husband, Lionel of Antwerp, would have worn livery and there are records of sums of money being given to him to buy clothes.
The idea of livery also carried over to the army, where each lord had his own retinue of soldiers. In 1346 the Welsh soldiers in the retinue of Edward, Prince of Wales, wore a short white coat with a hood.
Sources:
A Dictionary of Medieval Terms and Phrases by Christopher Corèdon and Ann Williams
The Time-Traveller’s Guide to Medieval England by Ian Mortimer
A Social History of England 1200 – 1500 ed. W. Mark Ormrod and Rosemary Horrox
Henry of Lancaster’s Expedition to Aquitaine by Nicholas A. Gribit
April Munday is the author of the Soldiers of Fortune and Regency Spies series of novels, as well as standalone novels set in the fourteenth century.
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A Writer's Perspective 
I suppose the equivalent today is uniforms.
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Yes, I think so. It would be interesting to know when members of households stopped wearing livery, but I didn’t come across any references to that.
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I wonder why retainers didn’t remove their livery before committing crimes, so as to be less recognizable.
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My guess is that it was because (a) the crimes weren’t planned ahead of time and (b) those were their clothes. Remove them and they’d be running around in the altogether. In a chilly country that’s full of thorns.
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They might not have known they were going to commit a crime. It was often spur of the moment stuff.
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