Citizenship of the United States
A person who is considered a citizen by more than one nation has "dual citizenship". It is possible for a United States citizen to have dual citizenship; this can be achieved in various ways, such as by birth in the United States to a parent who is a citizen of a foreign country (or in certain circumstances the foreign nationality may be transmitted even by a grandparent) by birth in another country to a parent(s) who is/are a United States citizen/s, or by having parents who are citizens of different countries. Anyone who becomes a naturalized U.S. citizen is required to renounce any prior "allegiance" to other countries during the naturalization ceremony; however, this renunciation of allegiance renunciation of citizenship to those countries.
Latvian nationality law
Dual citizenship is not prohibited by Latvian citizenship law. According to the amendments to the Citizenship Law which came into force on 1 October 2013, citizenship of Latvia may be retained for persons who have acquired the citizenship of:
Children of citizens of Latvia may hold dual citizenship with any country. Some countries, such as Japan, however, do not permit their nationals to also, after reaching adulthood, hold a foreign citizenship. A dual Latvian-Japanese national must declare, to Japan's Ministry of Justice, his or her intention as to which citizenship to keep, before turning 22.