14 October 1912 is considered the date of the official opening of Riga Zoological Garden, since on that day the certificate of its acceptance was signed in working atmosphere. The Society “Zooloģiskais dārzs Rīgā” (Zoological Garden in Riga) established a very modern zoological garden on donations.
- The rapid development of the zoological garden was interrupted by World War I, at the end of 1917 the institution was actually closed. Some animals were transported to Germany, the rest had to be disposed of.
- Since 1921 the territory of Riga Zoological Garden was transferred to the Department of Social Support that organised camps for children there.
- A zoological garden resumed work in a small part of the former territory on 24 September 1933. Previous expositions were restored and new ones created by society “Latvijas zooloģiskais dārzs” (Zoological Garden of Latvia), the zoo flourished once again and by 1940 occupied all of its former territory.
- Riga Zoological Garden continued its operation during World War II, and at the end of the war employees were able to prevent transportation of its collection to Germany.
- During the Soviet time despite limited circumstances the collection of animals was diverse, and the zoo was one of the best in the Soviet Union.
- At the time Latvia regained independence, buildings and communications of Riga Zoological Garden were in a state of considerable neglect. Due to state support, support from the city and sponsors, creative employees with numerous ideas it was possible to implement changes at the zoo and improve it.
In November 1992 Riga Zoological Garden joined the European Association of Zoos and Aquaria (EAZA). In December 1992 the Supreme Council of the Republic of Latvia took a decision to rename the zoo Riga National Zoological Garden.