In 1892 he returned to Philadelphia and began his career as a sculptor in earnest. His first major commission, won in a national competition, was for a larger-than-life-size statue of Dr. Samuel Gross (1895–97) for the National Mall in Washington, D.C.. Calder replicated the pose of Dr. Gross from Eakins's 1876 painting The Gross Clinic. That was followed by a set of twelve larger-than-life-size statues of Presbyterian clergymen for the facade of the Witherspoon Building (1898–99) in Philadelphia.
In 1912, he was named acting-chief (under Karl Bitter) of the sculpture program for the Panama-Pacific Exposition, a World's Fair to open in San Francisco, California in February 1915. He obtained a studio in NYC and there employed the services of model Audrey Munson who posed for him – Star Maiden (1913–15) – and a host of other artists. For the Exposition, Calder completed three massive sculpture groups, The Nations of the East and The Nations of the West, which crowned triumphal arches, and a fountain group, The Fountain of Energy. Following Bitter's sudden death in April 1915, Calder completed the Depew Memorial Fountain (1915–19) in Indianapolis, Indiana.
Hermon Atkins MacNeil and Calder were commissioned to create larger-than-life-size sculptures for the Washington Square Arch in New York City. George Washington as Commander-in-Chief, Accompanied by Fame and Valor (1914–16) was sculpted by MacNeil; and George Washington as President, Accompanied by Wisdom and Justice (1917–18) by Calder. These are sometimes referred to as Washington at War and Washington at Peace.
He was one of a dozen sculptors invited to compete in Oklahoma's Pioneer Woman statue competition in 1927, which was won by Bryant Baker. That year he was also commissioned by the Berkshire Museum to sculpt the woodwork and fountain of the Museum's Ellen Crane Memorial Room in Pittsfield, Massachusetts. An institution that would also see his more famous son, Alexander, accept his first public commission in the 1930s with a pair of mobiles for the Museum's new theater.
In 1929, he won the national competition for a monumental statue of Leif Eriksson, to be given by the United States to Iceland in commemoration of the 1000th anniversary of the Icelandic Parliament. Standing before the Hallgrímskirkja, the Lutheran cathedral in Reykjavík, and facing west toward the Atlantic Ocean and Greenland, the Leif Eriksson Memorial (1929–32) has become as iconic for Icelanders as the Statue of Liberty is for Americans.
The Nations of the West (1915), Panama-Pacific International Exposition, San Francisco, California. This massive sculpture group crowned the Arch of the Setting Sun. A second group, The Nations of the East (including a life-size elephant), crowned the Arch of the Rising Sun.
Twelve figures of clergymen, Witherspoon Building, Philadelphia, Pennsylvania, 1898–99, Joseph Miller Huston, architect. Six were removed in 1961, and are now on display in the garden of Presbyterian Historical Society, Philadelphia:
1968 U.S. postage stamp based on Calder's Leif Eriksson Memorial (1929–32) in Reykjavík, Iceland.
Armstrong, Craven et al., 200 Years of American Sculpture, Whitney Museum of Art, NYC, 1976
Bach, Penny Balkin, Public Art in Philadelphia, Temple University Press, Philadelphia, Pennsylvania, 1992
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Craven, Wayne, Sculpture in America, Thomas Y Crowell Co, New York 1968
Fairmount Park Art Association, Sculpture of a City: Philadelphia's Treasures in Bronze and Stone, Walker Publishing Co., Inc, New York. NY 1974
Falk, Peter Hastings, ed., Who was Who in American Art, Sound View Press, Madison Connecticut, 1985
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