In England the name was used by the Normans and became very popular due to Saint Thomas Becket, a 12th-century archbishop of Canterbury and martyr. It was reliably among the top five most common English names for boys from the 13th to the 19th century, and it has remained consistently popular to this day.
Another notable saint by this name was the 13th-century Italian philosopher and theologian Thomas Aquinas, who is regarded as a Doctor of the Church. Other famous bearers include philosopher Thomas Hobbes (1588-1679), American president Thomas Jefferson (1743-1826), novelist Thomas Hardy (1840-1928), and inventor Thomas Edison (1847-1931).
Due to the saint's popularity, the name came into general use in medieval Europe, especially in Spain and France. It was also borne by a 16th-century king of Portugal who died in a crusade against Morocco.
Originally more common as a name for boys in America, it became more popular for girls in the 1960s. It began rapidly increasing after 1973, possibly due to a character (played by Natalie Wood) in the television movie The Affair. It reached an apex in the United States ranked 17th in 1990, though it has quickly fallen away since then.