A mixture of fresh water and wine vinegar, sweetened with a little honey and flavored with herbs. Tangy and refreshing, it was the disinfected water and refreshment of the common people and the army — the sober antithesis of banquet wine.

Why this dish? Caesar was noted for his sobriety in wine, in contrast to his contemporaries. Posca — water mixed with vinegar — was THE drink of the soldier and the temperate man: thirst-quenching, it purified questionable water from the countryside, accompanying the legions from Gaul to Egypt.

Let others wallow in pure wine until they lose their wits — I, in the field, drink posca like my soldiers. A dash of vinegar in well water, and it becomes safe, fit to quench thirst without clouding the mind or the hand that holds the sword. Add a spoonful of honey if the palate objects, a few herbs for freshness. A man who would command others must first know how to command himself: that begins with his cup.

How it was made : Posca was so tied to the army that it was sometimes called 'the soldier's wine.' It is said that a legionary offered this drink during the crucifixion of Christ. Acidic and antiseptic, it made stagnant water potable — a sanitary measure ahead of its time.

The contemporary twist : Served as a summer shrub over crushed ice, with a lemon slice and mint sprig — the Roman ancestor of switchel or vinegar kombucha.

Sources : Plutarch, Life of Caesar (sobriety) · Suetonius, Lives of the Twelve Caesars

Julius Caesar · Charactorium