In Finland, a person must have a surname and at least one given name with up to four given names permitted. Surnames are inherited either patrilineally or matrilineally, while given names are usually chosen by a person's parents. Finnish names come from a variety of dissimilar traditions that were consolidated only in the early 20th century. The first national act on names came into force in 1921, and it made surnames mandatory. Between 1930 and 1985, the Western Finnish tradition whereby a married woman took her husband's surname was mandatory. Previously in Eastern Finland, this was not necessarily the case. On 1 January 2019, the reformed Act on Forenames and Surnames came into force.