The population of the town has been predominantly Hungarian at least since the late Middle Ages. The first detailed description of the town came from a charter of King Charles I of Hungary from 1341 when the king gave the estate of "Pókafölde" to comes Tamás. In the middle of the 15th century Szerdahely became an "oppidum", or market town. The first conscription of the population happened in 1574 (26 royal serf families and 3 noble families). The next conscription in 1646 indicates that most citizen were craftsmen. The town was under the feudal jurisdiction of the Pálffy family between 1600 and 1848. Many Jews came in the 18th century. In 1880 the town had 4182 inhabitants out of which 3531 (84.43%) were Hungarian and 416 (9.95%) were German by mother tongue. The number of the Jewish population was 1,874 (44.81%). In 1910 there were 4,679 (98.26%) Hungarian speakers (by mother tongue) from a total population of 4,762. In 1930, the town had 5,706 inhabitants, including 2,944 (51.6%) Hungarians, 2,186 (38.31%) Jews (mostly Hungarian-speaking) and 503 (8.82%) Slovaks. According to the 2001 census, 18,756 Hungarians, 3,588 Slovaks, 353 Romani people, 147 Czechs and 24 Germans live in the city, meaning a Hungarian majority of over 80%, one of the highest proportions of any municipality in the country.