[3] Later he was elected to the council of the Postmen's Union and was appointed head of the Södermanland district of the Social Democratic Party.

[3] Lundkvist was elected to the Parliament in 1959 for the Social Democratic Party and served there until 1986.

[1][2] In this capacity, he was responsible for civil defense and municipality and county councils, and his term ended in 1967.

[1][2] During his term as agriculture minister Lundkvist signed the Nordic Environmental Protection Convention on behalf of Sweden on 19 February 1974.

[5][6] In August 1984 Agriculture Minister Lundkvist initiated meetings with other Scandinavian countries, Austria, Canada, France, the Netherlands, Switzerland, and West Germany to discuss the limits of vehicle emissions as a response to the European Economic Community's decision on the topic dated May 1984.

[5][6] In May 1985 one of the largest demonstrations in the history of Sweden took place in Stockholm with the participation of nearly 25,000 farmers who marched to the headquarters of the Social Democratic Party.