Red coat, also referred to as redcoat or scarlet tunic, is a military garment formerly much used by British infantry servicemen, so customarily that the term became a common synecdoche for the servicemen themselves.
The red coat was widely (though not exclusively) used by the infantry units of the British military, including the British Army and Royal Marines, from the 16th to 19th centuries. The garment was also widely used by the British Colonial Auxiliary Forces and the British Indian Army during the 18th and 19th centuries. Though, by the 20th century, the red coat was abandoned for practical duties in favour of khaki by all British Empire military units, it continues to be used for ceremonial full dress and mess dress uniforms in many countries of the Commonwealth of Nations.
The usage of red coats by English soldiers dates back to the Tudor period, when the Yeomen of the Guard and the Yeomen Warders were both equipped in the royal colours of the House of Tudor, red and gold. During the Tudor conquest of Ireland and the Wars of the Three Kingdoms, units of English soldiers were equipped in red coats, most notably the New Model Army, which fought on the Parliamentary side.
From the mid-17th century to the 19th century, the uniform of most British soldiers (apart from artillery, rifles and light cavalry) included a madder red coat or coatee. From 1873 onwards, the more vivid shade of scarlet was adopted for all ranks, having previously been worn only by officers, sergeants and all ranks of some cavalry regiments.
History
Earlier instances
There had been instances of red military clothing pre-dating its general adoption by the New Model Army. The uniforms of the Yeomen of the Guard and the Yeomen Warders, both formed in 1485, have traditionally been in Tudor red and gold. The Gentlemen Pensioners of King James I wore red uniforms with yellow feathers in their hats. At the Battle of Edgehill, the first battle of the English Civil War, Royalist troops wore red coats, as did at least two Parliamentary regiments. However, none of these examples constituted the national uniform that the red coat was later to become.
16th century
In the Kingdom of Ireland, during the reign of Queen Elizabeth I, the soldiers of the queen's Lord-Lieutenant were occasionally referred to as "red coats" by Irish commentators, from the colour of their clothing. As early as 1561 the Irish named a victory over these troops as , literally meaning 'The Battle of the Red Cassocks' but usually translated as the Battle of the Red Sagums – sagum being a cloak. Note the Irish word is ("cassock") but the word may be translated as coat, cloak, or even uniform, in the sense that all of these troops were uniformly attired in red.
That the term "redcoat" was brought to Europe and elsewhere by Irish emigrants is evidenced by Irish nobleman and soldier Philip O'Sullivan Beare, who mentions the 'Battle of the Redcoats' event in his 1621 history of the Tudor conquest of Ireland, written in Latin in Spain. He wrote of it as "that famous victory which is called 'of the red coats' [] because among others who fell in battle were four hundred soldiers lately brought from England and clad in the red livery of the viceroy."
O'Sullivan alludes to two other encounters in which Irish rebels defeated English forces wearing 'red coats'. One concerns an engagement, twenty years later in 1581, during the Second Desmond Rebellion, in which he says, "a company of English soldiers, distinguished by their dress and arms, who were called 'red coats' [], and being sent to war [in Ireland] by the Queen were overwhelmed near Lismore by John Fitzedmund Fitzgerald, the seneschal." The other relates to a rout by William Burke, Lord of Bealatury, in 1599 of "English recruits clad in red coats" ().
English sources confirm that royal troops in Ireland wore red uniforms. In 1584, the Lord President of the Council informed the Sheriffs and Justices of Lancashire who were charged with raising 200 foot soldiers for service in Ireland that they should be furnished with "a cassocke of some motley, sad grene coller, or russett". Seemingly, russet was chosen. Again, in the summer of 1595, the Lord Deputy William Russell, writing to William Cecil, 1st Baron Burghley, about the relief of Enniskillen, mentions that the Irish rebel Hugh O'Neill, Earl of Tyrone, had "300 shot in red coats like English soldiers" – the inference being that English soldiers in Ireland were distinguished by their red uniforms.