Etymology of London

The name of London is derived from Londinium, established in the 1st century as a commercial centre in Roman Britain.

The etymology of the name is uncertain. The stems Londin- and Lundin- are the most prevalent in names used from Roman times onward. The 12th-century account Historia Regum Britanniae asserts that the city's name is derived from the name of King Lud who once controlled the city. A variety of other theories have been proposed since.

Richard Coates, in the 1998 article where he published his own theory of the etymology, lists all the known occurrences of the name up to around the year 900, in Greek, Latin, British and Anglo-Saxon.

Most of the older sources begin with Londin- (Λονδίνιον, Londino, Londinium etc.), though there are some in Lundin-; but later examples are mostly Lundon- or London-, and all the Anglo-Saxon examples have Lunden- with various terminations. He observes that the modern spelling with <o> derives from a medieval writing habit of avoiding <u> between letters composed of minims.

The earliest written mention of London occurs in a letter discovered in London in 2016. Dated AD 65/70-80, it reads "Londinio Mogontio" which translates to "'In London, to Mogontius"

Coates (1998) asserts that "It is quite clear that these vowel letters in the earliest forms, [viz., Londinium, Lundinium] both <o> and <u>, represent phonemically long vowel sounds". He observes that the ending in Latin sources before 600 is always -inium, which points to a British double termination -in-jo-n.

It has long been observed that the Anglo-Saxon form Lunden and the Welsh name Llundein cannot be directly derived from Common Brittonic *Londinjon. Following regular sound changes in the two languages, Welsh would have had *Lunnen or similar, and Old English would have *Lynden via i-mutation.

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