This surname is derived from the name of an ancestor. 'the son of Thomas,' from the diminutive Thomasin. A feminine Thomasina or Thomasine arose about the year 1350, and was popular as a font-name over the whole country till the 18th century. It is found in every register in every conceivable form, including Tamzen and Tomson. No doubt Thomasin, as a surname, has long been lost in Thomason or Thomson.

Thomasinus, varlet of Nicholas le Herier, Close Rolls, 4 Edward I.

1538. Married-Edward Bashe and Thomeson Agar: St. Dionis Backchurch (London).

1622. Buried-Tomson, d. John Moyer: St. Columb Major.

1623.-Tomson Simon, widow: ibid.

1657. Married-John Galley and Thomison Harte: St. Dionis Backchurch (London).

The surnames Thomas and Thompson both derive from the first name Thomas. The first name is one of the most ancient still in popular use, deriving from the ancient Aramaic where it meant ‘twin’. Its popularity in Western Europe stems from the Apostle of the same name, though in fact his real first name was Judas, and Thomas was only his nickname (given to distinguish him from Judas Iscariot).

In early days Thomas was not one of the great popular names, largely because of its link with ‘Doubting Thomas’-an unwise connotation in times when heretics were drawn and quartered. However, the fortunes of this name revived in England after 1170, when Thomas a Becket (who was later canonised) was murdered in Canterbury Cathedral at the instigation of his erstwhile friend, King Henry II. In fact, there are two other English St Thomas’s-St Thomas of Hereford, and Sir Thomas More (the hero of A Man for all Seasons) who was executed by King Henry VIII for refusing to admit the King as head of the Church.

The first name Thomas soon became the most popular in the land-witness its use in the phrase ‘every Tom, Dick and Harry’. It also became synonymous for anything male (thus we get the words Tomcat and Tomboy) and to this day it is the popular name for an English soldier (Tommie).

The first name Thomas, besides giving rise to the identical surname, also gave rise to many derivations from nicknames and variations. Thus we get Tomkin, which gave rise to Tomkins and Tomkinson. It is easy to see (in terms of English pronunciation) how the middle ‘p’ crept into these variant surnames-as in Thompkins. This also accounts for the ‘p’ in Thompson. Scottish pronunciation did not find a need for the intrusive ‘p’ and consequently we find the spelling Thom­son chiefly in Scotland.

The first name Thomas appears frequently in the Domesday Book, but it is nearly 200 years before we find the first use of the name as a surname. This is in the Hundred Rolls for Wiltshire in 1275, where one Walter Thomas is mentioned. Early in the next century the first Thompsons start appearing in the records. The first mention of the Scottish variation is in the records for Carrick in 1318, where one John Thomson is listed.

Scottish engineer Robert William Thomson was well ahead of his time. In 1845 he patented the pneumatic tyre, but nearly 50 years passed before Dunlop revived his invention for use in bicycles.

Newspaper magnate Roy Thomson (1894—1978), first Baron of Fleet, was the Canadian-born owner of the world’s largest publishing empire. In 1953 he moved to the UK and successively bought The Scotsman, The Sunday Times and The Times itself.

Scottish biologist Sir Charles Wyville Thomson (1830—82) led the famous Challenger expedition, the first important attempt at deep-sea exploration (1872—76). He discovered many life forms previously believed extinct, sometimes as far down as 650 fathoms.

The deadly Thompson sub-machine gun (popularly known as the ‘Tommy Gun’) was the co-invention of American Army engineer John Taliaferro Thompson (1860—1940).

Sir Benjamin Thompson (1753—1814), later Count Rumford, was a physicist, administrator and founder of the Royal Institution of Great Britain. His contributions to society include the cultivation of the potato, the invention of the kitchen range and a drip coffee pot, and the exposition of ‘Count Rumford’s Principle’ concerning the cure of smoking chimneys.

M. Thomson was one of over fifty pseudonyms used by the French writer and philosopher, Francois Marie Arouet, better known as Voltaire.

The youngest recorded university entrant was William Thomson, later Lord Kelvin, who entered Glasgow University in October 1834, aged 10 years, 4 months.

The English geologist Herbert Henry Thomas (1876—1935) established that the bluestones at Stonehenge had been transported 200 miles from the Prescelly Mountains in Wales where they had been quarried.

Physicist Sir Joseph John Thomson (1856—1940) established in 1897 that cathode rays were moving particles, later called electrons. This led to the discovery of isotopes and a greater understanding of atomic structure.

The world is full of Thomas/Thomson/Thompson-related places and geographic features. The United Kingdom alone has 21 towns ranging from Tomatin to Thomshill. Canada has 5 towns, the United States 28, Australia 3 and South Africa 2. Other places are spread all over the earth from Tomas Barron in Bolivia to Thomson Village in Singapore. Name-related lakes, rivers, mountains and islands are also common.

With about 245,000 namesakes Thomas is the 8th most popular surname in England and Wales, while with 190,000 Thompson ranks as 15th. (Thomas is not common enough throughout Scotland to be counted separately.) Thomson has about 42,000 namesakes which makes it Scotland’s 5th most popular surname. Thomas is notably popular in and around Cardiff where an estimated one in about 45 families bears the name, while Thompson’s most popular area is Teesside where one in 140 families is so named. Around the world Thomas’s and Thompsons (with or without the middle ‘p ’) are most common in Wellington (one in 191 families), while Melbourne and Sydney tie for second place with one in 210. The United States has an estimated total of just under 722,000 Thomas’s which makes this their 11th most popular surname, and just over 667,000 Thompsons which makes this their 16th most popular surname. Combined, they are in 6th place.