Born in Leipzig, Kingdom of Saxony, Weinert attended the Royal Academy of Art and Applied Art there[1] and then the Académie Royale des Beaux-Arts in Brussels, Belgium.

[2] In 1886, he emigrated to the United States, working first in San Francisco before moving to Chicago in 1892 to work on the World's Columbian Exposition where he met fellow sculptor Karl Bitter.

He later relocated to Washington, D.C. where, in April 1894, he was hired to work on the design of the Thomas Jefferson Building of the Library of Congress.

He was paid $10 per day (equivalent to $352 in 2023) to oversee a crew of modelers and carvers.

[3] He died on November 29, 1947, in his home studio on Grand Concourse in the Bronx.